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Cisco IOS Software Releases 12.3 T

Rate Based Satellite Control Protocol

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Table Of Contents

Rate Based Satellite Control Protocol

Contents

Restrictions for Rate Based Satellite Control Protocol

Information About Rate Based Satellite Control Protocol

IP over Satellite Links

Performance Enhancing Proxy over Satellite Links

RBSCP over Satellite Links

How to Configure Rate Based Satellite Control Protocol

Configuring the RBSCP Tunnel

Prerequisites

What to Do Next

Verifying that the RBSCP Tunnel Is Active

Verifying the RBSCP Traffic

Configuration Examples for Rate Based Satellite Control Protocol

Configuring the RBSCP Tunnel: Example

Configuring Routing for the RBSCP Tunnel: Example

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance

Command Reference

clear rbscp

debug tunnel rbscp

show rbscp

tunnel bandwidth

tunnel mode

tunnel rbscp ack_split

tunnel rbscp delay

tunnel rbscp input_drop

tunnel rbscp long_drop

tunnel rbscp report

tunnel rbscp window_stuff


Rate Based Satellite Control Protocol

Rate Based Satellite Control Protocol (RBSCP) was designed for wireless or long-distance delay links with high error rates, such as satellite links. Using tunnels, RBSCP can improve the performance of certain IP protocols, such as TCP and IP Security (IPSec), over satellite links without breaking the end-to-end model.

Feature History for Rate Based Satellite Control Protocol

Release
Modification

12.3(7)T

This feature was introduced.


Finding Support Information for Platforms and Cisco IOS Software Images

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Contents

•Restrictions for Rate Based Satellite Control Protocol

•Information About Rate Based Satellite Control Protocol

•How to Configure Rate Based Satellite Control Protocol

•Configuration Examples for Rate Based Satellite Control Protocol

•Additional References

•Command Reference

Restrictions for Rate Based Satellite Control Protocol

•RBSCP was designed for wireless or long-distance delay links with high error rates such as satellite links. If you do not have long-distance delay links with high error rates, do not implement this feature.

•If IP access lists (ACLs) are configured on an interface that is used by an RBSCP tunnel, the RBSCP IP protocol (199) must be allowed to enter and exit that interface or the tunnel will not function.

•RBSCP has some performance limitations because traffic through the tunnel is process-switched.

Information About Rate Based Satellite Control Protocol

To configure the RBSCP, you should understand the following concepts:

•IP over Satellite Links

•Performance Enhancing Proxy over Satellite Links

•RBSCP over Satellite Links

IP over Satellite Links

Satellite links have several characteristics that affect the performance of IP protocols over the link. Figure 1 shows that satellite links can have a one-way delay of 275 milliseconds. A round-trip time (RTT) of 550 milliseconds is a very long delay for TCP. Another issue is the high error rates (packet loss rates) that are typical of satellite links as compared to wired links in LANs. Even the weather affects satellite links, causing a decrease in available bandwidth, and an increase in RTT and packet loss.

Figure 1 Typical Satellite Link

Long RTT keeps TCP in a slow start mode, which increases the time before the satellite link bandwidth is fully used. TCP and Stream Control Transmission Protocol (SCTP) interpret packet loss events as congestion in the network and start to perform congestion recovery procedures, which reduce the traffic being sent over the link.

Although available satellite link bandwidths are increasing, the long RTT and high error rates experienced by IP protocols over satellite links are producing a high bandwidth-delay product (BDP).

Performance Enhancing Proxy over Satellite Links

To address the problem of TCP being kept in a slow start mode when a satellite link is used, a disruptive performance enhancing proxy (PEP) solution is introduced into the network. In Figure 2 you can see that the transport connection is broken up into three sections with hosts on the remote side connecting to the Internet through their default router. The router sends all Internet-bound traffic to the TCP PEP, which terminates the TCP connection to the Internet. The PEP generates a local TCP ACK (TCP spoofing) for all data. Traffic is buffered and retransmitted through a single PEP protocol connection over the satellite link. The second PEP receives the data from the satellite link and retransmits the data over separate TCP connections to the Internet. TCP transmission is disrupted, so dropped packets are not interpreted as TCP congestion and can be retransmitted from buffered data. Minimal TCP ACKs and reduced TCP slow starts allow more bandwidth to be used.

Figure 2 Disruptive TCP PEP Solution

One of the disadvantages to using disruptive TCP PEP is the breaking of the end-to-end model. Some applications cannot work when the flow of traffic is broken, and the PEP has no provision for handling encrypted traffic (IPSec). New transport protocols such as SCTP require special handling or additional code to function with disruptive TCP PEP. An additional managed network component is also required at every satellite router.

RBSCP over Satellite Links

RBSCP has been designed to preserve the end-to-end model and provide performance improvements over the satellite link without using a PEP solution. IPSec encryption of clear-text traffic (for example a VPN service configuration) across the satellite link is supported. RBSCP allows two routers to control and monitor the sending rates of the satellite link, thereby increasing the bandwidth utilization. Lost packets are retransmitted over the satellite link by RBSCP preventing the end host TCP senders from going into slow start mode.

RBSCP is implemented using a tunnel interface as shown in Figure 3. The tunnel can be configured over any network interface supported by Cisco IOS software that can be used by a satellite modem or internal satellite modem network module. IP traffic is sent across the satellite link with appropriate modifications and enhancements that are determined by the router configuration. Standard routing or policy-based routing can be used to determine the traffic to be sent through the RBSCP tunnel.

Figure 3 Nondisruptive RBSCP Solution

RBSCP tunnels can be configured for any of the following features.

Time Delay

One of the RBSCP routers can be configured to hold frames due for transmission through the RBSCP tunnel. The delay time increases the RTT at the end host and allows RBSCP time to retransmit lost TCP frames or other protocol frames. If the retransmission is successful, it prevents lost frame events from reaching the end host where congestion procedures would be enabled. In some cases the retransmission can be completed by RBSCP without inserting the delay.

ACK Splitting

Performance improvements can be made for clear-text TCP traffic using acknowledgement (ACK) splitting in which a number of additional TCP ACKs are generated for each TCP ACK received. TCP will open a congestion window by one maximum transmission unit (MTU) for each TCP ACK received. Opening the congestion window results in increased bandwidth becoming available. Configure this feature only when the satellite link is not using all the available bandwidth. Encrypted traffic cannot use ACK splitting.

Window Stuffing

Clear-text TCP and SCTP traffic can benefit from the RBSCP window stuffing feature. RBSCP can buffer traffic so that the advertised window can be incremented up to the available satellite link bandwidth or the available memory in the router. The end host that sends the packets is fooled into thinking that a larger window exists at the receiving end host and sends more traffic. Use this feature with caution because the end host may send too much traffic for the satellite link to handle and the resulting loss and retransmission of packets may cause link congestion.

SCTP Drop Reporting

SCTP uses an appropriate byte counting method instead of ACK counting to determine the size of the transmission window, so ACK splitting does not work with SCTP. The RBSCP tunnel can generate an SCTP packet-dropped report for packets dropped across the satellite but not as a result of congestion loss. This SCTP drop reporting is on by default and provides a chance to retransmit the packet without affecting the congestion window size. Actual congestion losses are still reported, and normal recovery mechanisms are activated.

How to Configure Rate Based Satellite Control Protocol

This section contains the following tasks:

•Configuring the RBSCP Tunnel (required)

•Verifying that the RBSCP Tunnel Is Active (optional)

•Verifying the RBSCP Traffic (optional)

Configuring the RBSCP Tunnel

Perform this task to configure the RBSCP tunnel. Remember to configure the router at each end of the tunnel.

Prerequisites

Ensure that the physical interface to be used as the tunnel source in this task is already configured.

SUMMARY STEPS

1. enable

2. configure terminal

3. interface type number

4. ip unnumbered interface-type interface-number

5. tunnel source {ip-address | interface-type interface-number}

6. tunnel destination {hostname | ip-address}

7. tunnel bandwidth {receive | transmit} bandwidth

8. tunnel mode {aurp | cayman | dvmrp | eon | gre | gre multipoint | ipip [decapsulate-any] | iptalk | mpls | nos | rbscp}

9. tunnel rbscp ack_split split-size

10. tunnel rbscp delay

11. tunnel rbscp report

12. tunnel rbscp window_stuff step-size

13. exit

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

•Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

interface type number

Example:

Router(config)# interface tunnel 0

Specifies the interface type and number and enters interface configuration mode.

Step 4 

ip unnumbered interface-type interface-number

Example:

Router(config-if)# ip unnumbered Ethernet 1

Enables IP processing on an interface without assigning an explicit IP address.

•Whenever the unnumbered interface generates a packet (for example, for a routing update), it uses the address of the specified interface as the source address of the IP packet.

Step 5 

tunnel source {ip-address | interface-type interface-number}

Example:

Router(config-if)# tunnel source Ethernet 1

Configures the tunnel source.

•Use the ip-address argument to specify the IP address of the service provider.

•Use the interface-type and interface-number arguments to specify the interface to use. For RBSCP we recommend specifying an interface as the tunnel source.

Step 6 

tunnel destination {hostname | ip-address}

Example:

Router(config-if)# tunnel destination 172.17.2.1

Configures the tunnel destination.

•Use the hostname argument to specify the IP address of the service provider.

•Use the ip-address argument to specify the interface to use.

Step 7 

tunnel bandwidth {receive | transmit} bandwidth

Example:

Router(config-if)# tunnel bandwidth transmit 1000

Specifies the tunnel bandwidth to be used to transmit packets.

•Use the bandwidth argument to specify the bandwidth.

Note The receive keyword is no longer used.

Step 8 

tunnel mode {aurp | cayman | dvmrp | eon | gre | gre multipoint | ipip [decapsulate-any] | iptalk | mpls| nos | rbscp}

Example:

Router(config-if)# tunnel mode rbscp

Specifies the protocol to be used in the tunnel.

•Use the rbscp keyword to specify that RBSCP will be used as the tunnel protocol.

Step 9 

tunnel rbscp ack_split split-size

Example:

Router(config-if)# tunnel rbscp ack_split 6

(Optional) Enables TCP acknowledgement (ACK) splitting with RBSCP tunnels.

•Use the split-size argument to specify the number of ACKs to send for every ACK received.

•The default number of ACKs is 4.

Step 10 

tunnel rbscp delay

Example:

Router(config-if)# tunnel rbscp delay

(Optional) Enables RBSCP tunnel delay.

•Use this command only when the RTT is greater than 700 milliseconds.

Step 11 

tunnel rbscp report

Example:

Router(config-if)# tunnel rbscp report

(Optional) Reports dropped RBSCP packets to SCTP.

•Reporting dropped packets to SCTP provides better bandwidth use because SCTP tells the end hosts to retransmit the dropped packets and this prevents the end hosts from assuming that the network is congested.

Step 12 

tunnel rbscp window_stuff step-size

Example:

Router(config-if)# tunnel rbscp window_stuff 3

(Optional) Enables TCP window stuffing by increasing the value of the TCP window scale for RBSCP tunnels.

•Use the step-size argument to specify the step increment number.

Step 13 

exit

Example:

Router(config-if)# exit

Exits interface configuration mode and returns to global configuration mode.

•Repeat this step one more time to exit global configuration mode.

What to Do Next

This task must be repeated on the router on the other side of the satellite link. Substitute the sample IP addresses, host names, and other parameters for the appropriate values on the second router.

Verifying that the RBSCP Tunnel Is Active

Perform this task to verify that the RBSCP tunnel configured in the "Configuring the RBSCP Tunnel" task is active.

SUMMARY STEPS

1. enable

2. show rbscp [all | state | statistics] [tunnel tunnel-number]

DETAILED STEPS

Step 1 enable

Enables privileged EXEC mode. Enter your password if prompted. 

Router> enable

Step 2 show rbscp [all | state | statistics] [tunnel tunnel-number]

Use this command with the state and tunnel keywords to display information about the current state of the tunnel. In the following sample output the tunnel is shown in an open state. 

Router# show rbscp state tunnel 1


Tunnel1 is up, line protocol is up

RBSCP operational state:  OPEN

RBSCP operating mode: (264h) ack_split window_stuffing inorder SCTP_report

  window step: 1

  drop scale : 0

  ACK split size: 4

  input drop scale: 2

  initial TSN: 1h

  fuzz factor: 0

  max burst: tunnel 0, network 0

  next TSN: 1h

  next sequence: 16Bh

  current outstanding: 0

  max out per RTT: 2062500

  packets since SACK: 0

  cumulative ack: 0h

  TSN at SACK: 0h

  last cumulative ack: 0h

  last delivered TSN: 0h

  next FWDTSN corr: 0h

  RTO: 704 ms

  RTT: 550 ms     srtt_sa: 4391   srtt_sv: 3

  sentQ: num packets: 0, num bytes: 0

  tmitQ: num packets: 0, num bytes: 0

Use this command with the statistics and tunnel keywords to display statistical information about the tunnel. All counters display totals accumulated since the last clear rbscp command was issued. 

Router# show rbscp statistics tunnel 0


Tunnel0 is up, line protocol is up

RBSCP protocol statistics:

  Init FWD-TSNs sent 0, received 0

  TUNNEL-UPs sent 0, received 0

  CLOSEDs sent 0, received 0

  TSNs sent 0, resent 0, lost by sender 0

  TSNs received 0 (duplicates 0)

  FWD-TSNs sent 144 (heartbeats 0)

  FWD-TSNs received 0 (ignored 0)

  FWD-TSNs caused 0 packet drops, 0 whole window drops

  SACKs sent 0, received 0 (ignored 0)

  Recovered with RTX 0

  Received with delay 0

  Most released at once 0

  Failed sends into the: tunnel 1, network 0

  Dropped due to: excess delay 0, tmit queue full 0

  Max on any queue: num packets: 0, num bytes: 0

  Max outstanding: 0

Verifying the RBSCP Traffic

Perform this task to verify that the traffic is being transmitted through the RBSCP tunnel and across the satellite link.

SUMMARY STEPS

1. enable

2. show interfaces tunnel number [accounting]

DETAILED STEPS

Step 1 enable

Enables privileged EXEC mode. Enter your password if prompted: 

Router> enable

Step 2 show interfaces tunnel number [accounting]

Use this command to show that traffic is being transmitted through the RBSCP tunnel: 

Router# show interfaces tunnel 0


Tunnel0 is up, line protocol is down 

  Hardware is Tunnel

  Internet address is 172.17.1.4/24

  MTU 1514 bytes, BW 9 Kbit, DLY 500000 usec, 

     reliability 255/255, txload 1/255, rxload 1/255

  Encapsulation TUNNEL, loopback not set

  Keepalive not set

  Tunnel source 172.17.1.2, destination 172.20.1.3

  Tunnel protocol/transport RBSCP/IP, key disabled, sequencing disabled

  Tunnel TTL 255

  Checksumming of packets disabled

  Tunnel transmit bandwidth 1000 (kbps)

  Tunnel receive bandwidth 8000 (kbps)

RBSCP operational state:  invalid (0h)

RBSCP operating mode: (2EEh) delay dual_delay drop_long_delay ack_split window_t

  window step: 3

  drop scale : 0

  ACK split size: 6

  input drop scale: 5

  initial TSN: 1h

  fuzz factor: 0

  next TSN: 1h

  next sequence: 1h

  current outstanding: 0

  max out per RTT: 550000

  packets since SACK: 0

  cumulative ack: 0h

  TSN at SACK: 1h

  last cumulative ack: 0h

  last delivered TSN: 0h

  next FWDTSN corr: 0h

  RTO: 704 ms

  RTT: 550 ms     srtt_sa: 0      srtt_sv: 4

  sentQ: num packets: 0, num bytes: 0

  tmitQ: num packets: 0, num bytes: 0


  Last input never, output never, output hang never

  Last clearing of "show interface" counters never

  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

  Queueing strategy: fifo

  Output queue: 0/0 (size/max)

  5 minute input rate 0 bits/sec, 0 packets/sec

  5 minute output rate 0 bits/sec, 0 packets/sec

     0 packets input, 0 bytes, 0 no buffer

     Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort

     0 packets output, 0 bytes, 0 underruns

     0 output errors, 0 collisions, 0 interface resets

     0 output buffer failures, 0 output buffers swapped out

Configuration Examples for Rate Based Satellite Control Protocol

This section contains the following configuration examples:

•Configuring the RBSCP Tunnel: Example

•Configuring Routing for the RBSCP Tunnel: Example

Configuring the RBSCP Tunnel: Example

In the following example, Router 1 and Router 2 are configured to send traffic through an RBSCP tunnel over a satellite link.

Router 1 

interface Tunnel 0

 ip unnumbered ethernet1

 tunnel source ethernet1

 tunnel destination 172.17.2.1

 tunnel bandwidth transmit 1000

 tunnel mode rbscp

 tunnel rbscp ack_split 6

 tunnel rbscp report

!

interface ethernet1

 description Satellite Link

 ip address 172.20.1.2 255.255.255.0

Router 2 

interface Tunnel 0

 ip unnumbered ethernet1

 tunnel source ethernet1

 tunnel destination 172.20.1.2

 tunnel bandwidth transmit 1000

 tunnel mode rbscp

 tunnel rbscp ack_split 6

 tunnel rbscp report

!

interface ethernet1

 description Satellite Link

 ip address 172.17.2.1 255.255.255.0

Configuring Routing for the RBSCP Tunnel: Example

To control the type of traffic that uses the RBSCP tunnel, you must configure the appropriate routing. If you want to direct all traffic through the tunnel, you can configure a static route.

Note Remember to configure the tunnel interface as passive if dynamic routing protocols are used to prevent routing flaps.

The following example shows how to use policy based routing to route some specific protocol types through the tunnel. In this example, an extended access list allows TCP, Stream Control Transmission Protocol (SCTP), Encapsulating Security Payload (ESP) protocol, and Authentication Header (AH) traffic to travel through the tunnel. All IP traffic is denied.

Router 1 (Local Side) 

interface Tunnel1

 ip unnumbered FastEthernet1/1

 tunnel source FastEthernet1/1

 tunnel destination 10.12.0.20

 tunnel mode rbscp

 tunnel ttl 5

 tunnel bandwidth transmit 30000

 tunnel rbscp window_stuff 1

 tunnel rbscp ack_split 4

!

interface FastEthernet0/0

 ip address 10.13.0.1 255.255.255.0

 ip policy route-map rbscp-pbr

 duplex auto

 speed auto

!

interface FastEthernet1/1

 description Satellite Link

 ip address 10.12.0.1 255.255.255.0

 duplex auto

 speed auto

!

ip route 10.15.0.0 255.255.255.0 FastEthernet1/1

!

ip access-list extended rbscp-acl

 permit tcp any 10.15.0.0 0.0.0.255

 permit 132 any 10.15.0.0 0.0.0.255

 permit esp any 10.15.0.0 0.0.0.255

 permit ahp any 10.15.0.0 0.0.0.255

 deny ip any any

!

!

route-map rbscp-pbr permit 10

 match ip address rbscp-acl

 set interface Tunnel1

Router 2 (Remote Side) 

ip dhcp pool CLIENT

 import all

 network 10.15.0.0 255.255.255.0

 default-router 10.15.0.1

 domain-name engineer.chicago.il.us

 dns-server 10.10.0.252

!

interface Tunnel1

 ip unnumbered FastEthernet0/1

 tunnel source FastEthernet0/1

 tunnel destination 10.12.0.1

 tunnel mode rbscp

 tunnel ttl 5

 tunnel bandwidth transmit 30000

 tunnel rbscp window_stuff 1

 tunnel rbscp ack_split 4

!

interface FastEthernet0/0

 description Local LAN

 ip address 10.15.0.1 255.255.255.0

 ip policy route-map rbscp-pbr

 duplex auto

 speed auto

!

interface FastEthernet0/1

 description Satellite Link

 ip address 10.12.0.20 255.255.255.0

 duplex auto

 speed auto

!

ip route 0.0.0.0 0.0.0.0 FastEthernet0/1

!

ip access-list extended rbscp-acl

 permit tcp any any

 permit 132 any any

 permit esp any any

 permit ahp any any

 deny ip any any

!

route-map rbscp-pbr permit 10

 match ip address rbscp-acl

 set interface Tunnel1

Additional References

The following sections provide references related to Rate Based Satellite Control Protocol.

Related Documents

Related Topic
Document Title

Tunnel interface commands: complete command syntax, command mode, defaults, usage guidelines, and examples

Cisco IOS Interface and Hardware Component Command Reference, Release 12.3 T

Tunnel configuration

The chapter "Configuring Logical Interfaces" in the Cisco IOS Interface and Hardware Component Configuration Guide


Standards

Standards
Title

No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.

—


MIBs

MIBs
MIBs Link

No new or modified MIBs are supported by this feature, and support for existing MIBs has not been modified by this feature.

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://www.cisco.com/go/mibs


RFCs

RFCs
Title

RFC 1323

TCP Extensions for High Performance

RFC 2018

TCP Selective Acknowledgment Options


Technical Assistance

Description
Link

Technical Assistance Center (TAC) home page, containing 30,000 pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content.

http://www.cisco.com/public/support/tac/home.shtml


Command Reference

This section documents new and modified commands only.

•clear rbscp

•debug tunnel rbscp

•show rbscp

•tunnel bandwidth

•tunnel mode

•tunnel rbscp ack_split

•tunnel rbscp delay

•tunnel rbscp input_drop

•tunnel rbscp long_drop

•tunnel rbscp report

•tunnel rbscp window_stuff

clear rbscp

To reset and restart a Rate Based Satellite Control Protocol (RBSCP) tunnel, use the clear rbscp command in privileged EXEC mode.

clear rbscp [tunnel tunnel-number]

Syntax Description

tunnel

(Optional) Resets and restarts the RBSCP tunnel interface specified in the tunnel-number argument. If a tunnel interface is not specified, all RBSCP tunnels are reset and restarted.

•tunnel-number—Number of the tunnel interface in the range from 0 to 2147483647.


Command Modes

Privileged EXEC

Command History

Release
Modification

12.3(7)T

This command was introduced.


Usage Guidelines

The clear rbscp command resets the tunnel interface to its initial state and this clears RBSCP statistical information. Use this command for troubleshooting issues with RBSCP tunnels.

Examples

The following example shows how to clear the RBSCP statistics. A show rbscp statistics command is issued first to display the current RBSCP counters for tunnel interface 0. The clear rbscp command is then entered to reset and restart tunnel interface 0. All the counters for tunnel interface 0 are reset to zero. A final show rbscp statistics command is issued to show that all the counters, except those counters that show the packets sent since the clearing, are reset to zero. 

Router# show rbscp statistics tunnel 0


Tunnel0 is up, line protocol is up

RBSCP protocol statistics:

  Init FWD-TSNs sent 15, received 11

  TUNNEL-UPs sent 10, received 5

  CLOSEDs sent 3, received 2

  TSNs sent 40, resent 2, lost by sender 1

  TSNs received 36 (duplicates 2)

  FWD-TSNs sent 144 (heartbeats 2)

  FWD-TSNs received 120 (ignored 1)

  FWD-TSNs caused 3 packet drops, 0 whole window drops

  SACKs sent 10, received 6 (ignored 1)

  Recovered with RTX 1

  Received with delay 2

  Most released at once 5

  Failed sends into the: tunnel 1, network 0

  Dropped due to: excess delay 0, tmit queue full 0

  Max on any queue: num packets: 12, num bytes: 0

  Max outstanding: 0


Router# clear rbscp tunnel 0


Tunnel0: cleared statistics 


Router# show rbscp statistics tunnel 0


Tunnel0 is up, line protocol is up

RBSCP protocol statistics:

  Init FWD-TSNs sent 0, received 0

  TUNNEL-UPs sent 0, received 0

  CLOSEDs sent 0, received 0

  TSNs sent 0, resent 0, lost by sender 0

  TSNs received 0 (duplicates 0)

  FWD-TSNs sent 26 (heartbeats 0)

  FWD-TSNs received 0 (ignored 0)

  FWD-TSNs caused 0 packet drops, 0 whole window drops

  SACKs sent 0, received 0 (ignored 0)

  Recovered with RTX 0

  Received with delay 0

  Most released at once 0

  Failed sends into the: tunnel 0, network 0

  Dropped due to: excess delay 0, tmit queue full 0

  Max on any queue: num packets: 0, num bytes: 0

  Max outstanding: 0

Related Commands

Command
Description

show rbscp

Displays RBSCP state and statistical information.


debug tunnel rbscp

To turn on the debugging output for Rate Based Satellite Control Protocol (RBSCP) tunnels, use the debug tunnel rbscp command in privileged EXEC mode. To turn off debugging output, use the no form of this command.

debug tunnel rbscp [ack_split | detail | msg | rto | state | window]

no debug tunnel rbscp [ack_split | detail | msg | rto | state | window]

Syntax Description

ack_split

(Optional) Displays debugging messages about RBSCP ACK splitting.

detail

(Optional) Displays detailed debugging messages about RBSCP.

msg

(Optional) Displays debugging messages about the RBSCP messages.

rto

(Optional) Displays debugging messages about RBSCP round-trip times (RTTs) and retransmission timeouts (RTOs).

state

(Optional) Displays debugging messages about the RBSCP states.

window

(Optional) Displays debugging messages about RBSCP window stuffing.


Command Modes

Privileged EXEC

Command History

Release
Modification

12.3(7)T

This command was introduced.


Usage Guidelines

Use the debug tunnel rbscp command in privileged EXEC mode to troubleshoot RBSCP command operations.

Caution Use any debugging command with caution as the volume of output generated can slow or stop the router operations. We recommend that this command be used only under the supervision of a Cisco engineer.

Examples

The following example turns on debugging messages about RBSCP messages: 

Router# debug tunnel rbscp msg


Tunnel RBSCP message debugging is on

router#

*Mar  1 05:36:01.435: handling FWD_TSN: sequence=20h, tsn=0h

*Mar  1 05:36:03.371: rbscp_output_a_fwdtsn: tsn=0h, seq=Dh, for_hb=1

*Mar  1 05:36:10.835: handling FWD_TSN: sequence=21h, tsn=0h

*Mar  1 05:36:12.771: rbscp_output_a_fwdtsn: tsn=0h, seq=Eh, for_hb=1

*Mar  1 05:36:20.235: handling FWD_TSN: sequence=22h, tsn=0h

*Mar  1 05:36:22.171: rbscp_output_a_fwdtsn: tsn=0h, seq=Fh, for_hb=1

Note Note that the debug output will vary depending on what the router is configured to do after the debug command is entered.

Table 1 describes the significant fields shown in the display.

Table 1 debug tunnel rbscp msg Field Descriptions 

Field
Description

handling FWD_TSN

The router has received and is processing a FWD_TSN message from a peer with a sequence number of 20 hex and a Transport Sequence Number (TSN) of 0 hex.

rbscp_output_a_fwdtsn

The router is sending a FWD_TSN message to the peer with a TSN of 0 hex, a sequence number of 0D hex and it is for a heartbeat (equivalent of a keepalive).


The following example turns on debugging messages about RBSCP round-trip times and retransmission timeouts: 

Router# debug tunnel rbscp rto


Tunnel RBSCP RTT/RTO debugging is on

router#

*Mar  1 05:36:50.927: update_rtt: cur_rtt:549 ms:548 delay:0

*Mar  1 05:36:50.927: New RTT est:549 RTO:703

*Mar  1 05:37:00.327: update_rtt: cur_rtt:549 ms:548 delay:0

*Mar  1 05:37:00.327: New RTT est:549 RTO:703

*Mar  1 05:37:09.727: update_rtt: cur_rtt:549 ms:548 delay:0

*Mar  1 05:37:09.727: New RTT est:549 RTO:703

Table 2 describes the significant fields shown in the display.

Table 2 debug tunnel rbscp rto Field Descriptions 

Field
Description

update rtt: curr rtt

Displays the updated, previous, and current RTT, in milliseconds, and a number that represents the amount of additional delay from queuing.

New RTT est

Displays the estimated new RTT, in milliseconds.

RTO

Displays the new retransmission timeout, in milliseconds.



show rbscp

To display state and statistical information about Rate Based Satellite Control Protocol (RBSCP) tunnels, use the show rbscp command in user EXEC or privileged EXEC mode.

show rbscp {all | state | statistics} [tunnel tunnel-number]

Syntax Description

all

Displays both RBSCP state and RBSCP statistical information.

state

Displays the RBSCP state information.

statistics

Displays RBSCP statistical information.

tunnel

(Optional) Displays the RBSCP information for the tunnel interface specified in the tunnel-number argument. If a tunnel interface is not specified, information for all RBSCP tunnels is displayed.

•tunnel-number—Number of the tunnel interface in the range from 0 to 2147483647.


Command Modes

User EXEC
Privileged EXEC

Command History

Release
Modification

12.3(7)T

This command was introduced.


Usage Guidelines

The output of this command is most helpful to the person who has the task of configuring and monitoring RBSCP tunnels. The output shows various state and statistical information about RBSCP tunnels.

Examples

The following is sample output from the show rbscp all command: 

Router# show rbscp all


Tunnel0 is up, line protocol is up

RBSCP operational state:  IS OPENING

RBSCP operating mode: (264h) ack_split window_stuffing inorder SCTP_report

  window step: 1

  drop scale : 0

  ACK split size: 4

  input drop scale: 2

  initial TSN: 1h

  fuzz factor: 0

  next TSN: 1h

  next sequence: 1h

  current outstanding: 0

  max out per RTT: 68750

  packets since SACK: 0

  cumulative ack: 0h

  TSN at SACK: 1h

  last cumulative ack: 0h

  last delivered TSN: 0h

  next FWDTSN corr: 6h

  RTO: 704 ms

  RTT: 550 ms     srtt_sa: 0      srtt_sv: 4

  sentQ: num packets: 0, num bytes: 0

  tmitQ: num packets: 0, num bytes: 0


RBSCP protocol statistics:

  Init FWD-TSNs sent 0, received 0

  TUNNEL-UPs sent 0, received 0

  CLOSEDs sent 0, received 0

  TSNs sent 0, resent 0, lost by sender 0

  TSNs received 0 (duplicates 0)

  FWD-TSNs sent 63 (heartbeats 0)

  FWD-TSNs received 0 (ignored 0)

  FWD-TSNs caused 0 packet drops, 0 whole window drops

  SACKs sent 0, received 0 (ignored 0)

  Recovered with RTX 0

  Received with delay 0

  Most released at once 0

  Failed sends into the: tunnel 1, network 0

  Dropped due to: excess delay 0, tmit queue full 0

  Max on any queue: num packets: 0, num bytes: 0

  Max outstanding: 0

Table 3 describes the significant fields shown in the display.

Table 3 show rbscp all Field Descriptions

Field
Description

tunnel is {up | down}

Interface is currently active (up) or inactive (down).

line protocol is {up | down | administratively down}

Shows line protocol up if a valid route is available to the tunnel destination. Shows line protocol down if no route is available or if the route would be recursive.

RBSCP operational state

Indicates the current RBSCP state.

RBSCP operating mode

Indicates the RBSCP operating mode.

window step

Step size for the window scale.

drop scale

Scale factor for the number of bytes that can be queued before packets are dropped on the output side.

Ack split size

Number of TCP acknowledgements to send for every ack received.

input drop scale

Scale factor for the number of bytes that can be queued before packets are dropped on the input side.

initial TSN

Transport Sequence Number (TSN) of the first outgoing RBSCP/IP packet sent to a peer. RBSCP uses sequence numbers to ensure a reliable service. Peers will send the TSN back in the acknowledgment packet.

fuzz factor

Value added to the RBSCP delay clock to pad the delay when large round-trip time (RTT) fluctuations occur.

next TSN

TSN of the next outgoing RBSCP/IP packet.

next sequence

Next sequence number to use, in hex.

current outstanding

Current number of bytes that are in transit or are unacknowledged.

max out per RTT

Maximum number of bytes allowed to be sent out per RTT.

packets sent since SACK

Number of packets sent since an RBSCP Selective Acknowledgement (SACK).

cumulative ack

Cumulative acknowledgement point which is the highest in sequence TSN that was received from a peer.

TSN at SACK

Value of highest TSN for the last SACK that was received from a peer.

last cumulative ack

Last cumulative acknowledgement point that was received from the peer.

last delivered TSN

Last TSN received that was subsequently delivered to an upper level protocol.

next FWDTSN corr

Next FWD_TSN correlation entry to use.

RTO

Retransmission timeout, in milliseconds.

RTT

Round-trip time estimate, in milliseconds.

srtt_sa

Smoothed round-trip time average.

srtt_sv

Smoothed round-trip time variance.

sentQ

Number of packets and bytes sent but not yet acknowledged.

tmitQ

Number of packets and bytes ready to be sent.

Init FWD-TSNs

Number of TSNs sent and received for initializing the RBSCP tunnel.

TUNNEL-UPs

Number of TUNNEL_UP messages sent and received.

CLOSEDs

Number of CLOSED messages sent and received.

heartbeats

Heartbeats are equivalent to keepalive messages.

Recovered with RTX

Number of packets recovered using a retransmitted message.

Received with delay

Number of packets that included a delay value.

Most released at once

Maximum burst of packets sent in one interval.

Failed sends

Number of packets that were sent but failed because of an internal error, such as no route or the underlying interface is down.


The following is sample output from the show rbscp state command: 

Router# show rbscp state


Tunnel0 is up, line protocol is up

RBSCP operational state:  IS OPENING

RBSCP operating mode: (264h) ack_split window_stuffing inorder SCTP_report

  window step: 1

  drop scale : 0

  ACK split size: 4

  input drop scale: 2

  initial TSN: 1h

  fuzz factor: 0

  next TSN: 1h

  next sequence: 1h

  current outstanding: 0

  max out per RTT: 68750

  packets since SACK: 0

  cumulative ack: 0h

  TSN at SACK: 1h

  last cumulative ack: 0h

  last delivered TSN: 0h

  next FWDTSN corr: 0h

  RTO: 704 ms

  RTT: 550 ms     srtt_sa: 0      srtt_sv: 4

  sentQ: num packets: 0, num bytes: 0

  tmitQ: num packets: 0, num bytes: 0

The following is sample output from the show rbscp statistics command: 

Router# show rbscp statistics tunnel 0


Tunnel0 is up, line protocol is up

RBSCP protocol statistics:

  Init FWD-TSNs sent 0, received 0

  TUNNEL-UPs sent 0, received 0

  CLOSEDs sent 0, received 0

  TSNs sent 0, resent 0, lost by sender 0

  TSNs received 0 (duplicates 0)

  FWD-TSNs sent 136 (heartbeats 0)

  FWD-TSNs received 0 (ignored 0)

  FWD-TSNs caused 0 packet drops, 0 whole window drops

  SACKs sent 0, received 0 (ignored 0)

  Recovered with RTX 0

  Received with delay 0

  Most released at once 0

  Failed sends into the: tunnel 1, network 0

  Dropped due to: excess delay 0, tmit queue full 0

  Max on any queue: num packets: 0, num bytes: 0

  Max outstanding: 0

Related Commands

Command
Description

clear rbscp

Resets and restarts RBSCP tunnels.


tunnel bandwidth

To set the transmit bandwidth used by the tunnel interface, use the tunnel bandwidth command in interface configuration mode. To restore the default setting, use the no form of this command.

tunnel bandwidth {receive | transmit} bandwidth

no tunnel bandwidth

Syntax Description

receive

Specifies the bandwidth to be used to receive packets through the tunnel.

Note This keyword is no longer used and will be removed in future releases.

transmit

Specifies the bandwidth to be used to send packets through the tunnel.

bandwidth

Bandwidth, in kbps. Range is from 0 to 2147483647. Default is 8000.


Defaults

8000 kbps

Command Modes

Interface configuration

Command History

Release
Modification

12.3(7)T

This command was introduced.


Usage Guidelines

Use the tunnel bandwidth command to specify the capacity of the satellite link.

Examples

The following example shows how to set the satellite tunnel bandwidth to 1000 kbps for transmitting packets using Rate Based Satellite Control Protocol: 

Router(config)# interface tunnel 0

Router(config-if)# tunnel bandwidth transmit 1000

Related Commands

Command
Description

tunnel destination

Specifies the destination for a tunnel interface.

tunnel mode

Sets the encapsulation mode for a tunnel interface.

tunnel source

Sets the source address of a tunnel interface.


tunnel mode

To set the encapsulation mode for a tunnel interface, use the tunnel mode command in interface configuration mode. To restore the default mode, use the no form of this command.

tunnel mode {aurp | cayman | dvmrp | eon | gre | gre multipoint | ipip [decapsulate-any] | iptalk | mpls | nos | rbscp}

no tunnel mode

Syntax Description

aurp

AppleTalk Update-Based Routing Protocol.

cayman

Cayman TunnelTalk AppleTalk encapsulation.

dvmrp

Distance Vector Multicast Routing Protocol.

eon

EON compatible CLNS tunnel.

gre

Generic routing encapsulation protocol. This is the default.

gre multipoint

Multipoint GRE (mGRE).

ipip

IP-over-IP encapsulation.

•decapsulate-any—(Optional) Terminates any number of IP-in-IP tunnels at one tunnel interface. Note that this tunnel will not carry any outbound traffic; however, any number of remote tunnel endpoints can use a tunnel configured this way as their destination.

iptalk

Apple IPTalk encapsulation.

mpls

Multiprotocol Label Switching encapsulation.

nos

KA9Q/NOS compatible IP over IP.

rbscp

Rate Based Satellite Control Protocol (RBSCP).


Defaults

GRE tunneling

Command Modes

Interface configuration

Command History

Release
Modification

10.0

This command was introduced.

10.3

The following keywords were added:

•aurp

•dvmrp

•ipip

11.2

The optional decapsulate-any keyword was added.

12.2(13)T

The gre multipoint keyword was added.

12.3(7)T

The rbscp keyword was added.


Usage Guidelines

Source and Destination Address

You cannot have two tunnels that use the same encapsulation mode with exactly the same source and destination address. The workaround is to create a loopback interface and source packets off of the loopback interface.

Cayman Tunneling

Designed by Cayman Systems, Cayman tunneling implements tunneling to enable Cisco routers to interoperate with Cayman GatorBoxes. With Cayman tunneling, you can establish tunnels between two routers or between a Cisco router and a GatorBox. When using Cayman tunneling, you must not configure the tunnel with an AppleTalk network address.

DVMRP

Use DVMRP when a router connects to an mrouted router to run DVMRP over a tunnel. You must configure Protocol Independent Multicast (PIM) and an IP address on a DVMRP tunnel.

GRE with AppleTalk

GRE tunneling can be done between Cisco routers only. When using GRE tunneling for AppleTalk, you configure the tunnel with an AppleTalk network address. Using the AppleTalk network address you can ping the other end of the tunnel to check the connection.

Multipoint GRE

After enabling mGRE tunneling, you can enable the tunnel protection command, which allows you to associate the mGRE tunnel with an IP Security (IPSec) profile. Combining mGRE tunnels and IPSec encryption allows a single mGRE interface to support multiple IPSec tunnels, thereby simplifying the size and complexity of the configuration.

Note GRE tunnel keepalives configured using the keepalive command under a GRE interface are
supported only on point-to-point GRE tunnels.

RBSCP

RBSCP tunneling is designed for wireless or long-distance delay links with high error rates, such as satellite links. Using tunnels, RBSCP can improve the performance of certain IP protocols, such as TCP and IPSec, over satellite links without breaking the end-to-end model.

Examples

Cayman Tunneling

The following example shows how to enable Cayman tunneling: 

Router(config)# interface tunnel 0

Router(config-if)# tunnel source ethernet 0

Router(config-if)# tunnel destination 10.108.164.19

Router(config-if)# tunnel mode cayman

GRE Tunneling

The following example shows how to enable GRE tunneling: 

Router(config)# interface tunnel 0

Router(config-if)# appletalk cable-range 4160-4160 4160.19

Router(config-if)# appletalk zone Engineering

Router(config-if)# tunnel source ethernet0

Router(config-if)# tunnel destination 10.108.164.19

Router(config-if)# tunnel mode gre

Multipoint GRE Tunneling

The following example shows how to enable mGRE tunneling: 

interface Tunnel0

 bandwidth 1000

 ip address 10.0.0.1 255.255.255.0

! Ensures that longer packets are fragmented before they are encrypted; otherwise, the 
! receiving router would have to do the reassembly.

 ip mtu 1416

! Turns off split horizon on the mGRE tunnel interface; otherwise, EIGRP will not 
! advertise routes that are learned via the mGRE interface back out that interface.

 no ip split-horizon eigrp 1

 no ip next-hop-self eigrp 1

 delay 1000

! Sets the IPSec peer address to the Ethernet interface's public address.

 tunnel source Ethernet0

 tunnel mode gre multipoint

! The following line must match on all nodes that want to use this mGRE tunnel.

 tunnel key 100000

 tunnel protection ipsec profile vpnprof

RBSCP Tunneling

The following example shows how to enable RBSCP tunneling: 

Router(config)# interface tunnel 0

Router(config-if)# tunnel source ethernet 0

Router(config-if)# tunnel destination 10.108.164.19

Router(config-if)# tunnel mode rbscp

Related Commands

Command
Description

appletalk cable-range

Enables an extended AppleTalk network.

appletalk zone

Sets the zone name for the connected AppleTalk network.

tunnel destination

Specifies the destination for a tunnel interface.

tunnel protection

Associates a tunnel interface with an IPSec profile.

tunnel source

Sets the source address of a tunnel interface.


tunnel rbscp ack_split

To enable TCP acknowledgement (ACK) splitting for Rate Based Satellite Control Protocol (RBSCP) tunnels, use the tunnel rbscp ack_split command in interface configuration mode. To disable TCP acknowledgement splitting for RBSCP tunnels, use the no form of this command.

tunnel rbscp ack_split split-size

no tunnel rbscp ack_split split-size

Syntax Description

split-size

Number of ACKs to send for every ACK received. Range is from 1 to 32. Default is 4.


Defaults

TCP acknowledgement splitting for RBSCP tunnels is disabled.

Command Modes

Interface configuration

Command History

Release
Modification

12.3(7)T

This command was introduced.


Usage Guidelines

Performance improvements can be made for clear-text TCP traffic using ACK splitting where a number of additional TCP ACKs are generated for each TCP ACK received. TCP will open a congestion window by one maximum transmission unit (MTU) for each TCP ACK received. Opening the congestion window results in increased bandwidth becoming available. Use the tunnel rbscp ack_split command only when the satellite link is not using all the available bandwidth. Encrypted traffic cannot use ACK splitting.

Examples

The following example shows how to enable RBSCP tunnel TCP ACK splitting and configure three ACK packets to be sent for each ACK packet received: 

Router(config)# interface tunnel 0

Router(config-if)# tunnel rbscp ack_split 3

Related Commands

Command
Description

show rbscp

Displays state and statistical information about RBSCP tunnels.


tunnel rbscp delay

To enable the Rate Based Satellite Control Protocol (RBSCP) tunnel delay, use the tunnel rbscp delay command in interface configuration mode. To disable RBSCP tunnel delay, use the no form of this command.

tunnel rbscp delay

no tunnel rbscp delay

Syntax Description

This command has no arguments or keywords.

Defaults

RBSCP tunnel delay is disabled.

Command Modes

Interface configuration

Command History

Release
Modification

12.3(7)T

This command was introduced.


Usage Guidelines

Use the tunnel rbscp delay command only if the RBSCP tunnel has a round-trip time (RTT) over 700 milliseconds.

Examples

The following example shows how to enable the RBSCP tunnel delay: 

Router(config)# interface tunnel 0

Router(config-if)# tunnel rbscp delay

Related Commands

Command
Description

show rbscp

Displays state and statistical information about RBSCP tunnels.


tunnel rbscp input_drop

To configure the input queue size on a Rate Based Satellite Control Protocol (RBSCP) tunnel, use the tunnel rbscp input_drop command in interface configuration mode. To restore the default input queue size, use the no form of this command.

tunnel rbscp input_drop bw-delay-products

no tunnel rbscp input_drop

Syntax Description

bw-delay-products

Number of bandwidth delay products (BDP) bytes that can be queued before packets are dropped on the input side. Range from 1 to 10. Default is 2.


Defaults

Input queue size is 2 BDP bytes.

Command Modes

Interface configuration

Command History

Release
Modification

12.3(7)T

This command was introduced.


Usage Guidelines

Use the tunnel rbscp input_drop command to restrict the amount of data queued by the router. After the configured byte limit is reached, packets that would be encapsulated and sent via the tunnel are dropped on the input side. Congestion control of the satellite link is also provided by this command because the dropped packets will force the end hosts to reduce their sending rate of packets.

Use this command in conjunction with the tunnel rbscp long_drop command which allows packets that are waiting in an RBSCP tunnel encapsulation queue to be dropped after a period of time.

Examples

The following example shows how to set the RBSCP tunnel queue size to 5 BDP bytes: 

Router(config)# interface tunnel 0

Router(config-if)# tunnel rbscp input_drop 5

Related Commands

Command
Description

show rbscp

Displays state and statistical information about RBSCP tunnels.

tunnel rbscp long_drop

Allows packets to be dropped after waiting in the RBSCP tunnel encapsulation queue for too long.


tunnel rbscp long_drop

To allow packets to be dropped that have been queued too long for Rate Based Satellite Control Protocol (RBSCP) tunnel encapsulation, use the tunnel rbscp long_drop command in interface configuration mode. To disable the dropping of queued packets, use the no form of this command.

tunnel rbscp long_drop

no tunnel rbscp long_drop

Syntax Description

This command has no arguments or keywords.

Defaults

No queued packets are dropped.

Command Modes

Interface configuration

Command History

Release
Modification

12.3(7)T

This command was introduced.


Usage Guidelines

The tunnel rbscp long_drop command allows the transmitting router to drop packets that have been waiting in the queue for RBSCP tunnel encapsulation for a long time. The period of time after which packets are dropped is determined using the round-trip time (RTT) estimate of the tunnel.

Use this command in conjunction with the tunnel rbscp input_drop command which configures the size of the input queue. After the configured byte limit of the input queue is reached, packets are dropped.

Examples

The following example shows how to allow packets to be dropped when they have been queued for RBSCP tunnel encapsulation too long: 

Router(config)# interface tunnel 0

Router(config-if)# tunnel rbscp long_drop

Related Commands

Command
Description

show rbscp

Displays state and statistical information about RBSCP tunnels.

tunnel rbscp input_drop

Configures the input queue size on an RBSCP tunnel.


tunnel rbscp report

To report dropped Rate Based Satellite Control Protocol (RBSCP) packets to the Stream Control Transmission Protocol (SCTP), use the tunnel rbscp report command in interface configuration mode. To disable dropped-packet reporting to SCTP, use the no form of this command.

tunnel rbscp report

no tunnel rbscp report

Syntax Description

This command has no arguments or keywords.

Defaults

RBSCP dropped-packet reporting is enabled.

Command Modes

Interface configuration

Command History

Release
Modification

12.3(7)T

This command was introduced.


Usage Guidelines

Use the tunnel rbscp report command to provide early reporting of dropped RBSCP packets to SCTP instead of attempting retransmission of the packets at the router. SCTP will inform the end hosts of the dropped packets and allow the end hosts to retransmit the packets. Reporting dropped packets through SCTP provides better throughput because the packet dropping is not assumed to be caused by congestion.

Examples

The following example shows how to disable the SCTP drop reporting (reporting is enabled by default): 

Router(config)# interface tunnel 0

Router(config-if)# no tunnel rbscp report

Related Commands

Command
Description

show rbscp

Displays state and statistical information about RBSCP tunnels.


tunnel rbscp window_stuff

To enable window stuffing by increasing the value of the window scale for Rate Based Satellite Control Protocol (RBSCP) tunnels, use the tunnel rbscp window_stuff command in interface configuration mode. To restore the default window scale value, use the no form of this command.

tunnel rbscp window_stuff step-size

no tunnel rbscp window_stuff

Syntax Description

step-size

Increment step size for the window scale. Range is from 1 to 20. Default is 1.


Defaults

Window stuffing is disabled.

Command Modes

Interface configuration

Command History

Release
Modification

12.3(7)T

This command was introduced.


Usage Guidelines

Use the tunnel rbscp window_stuff command to make the sending host believe that the receiving host has a larger window by artificially increasing the window size. RBSCP buffers the additional window and which be configured up to the satellite link bandwidth or the memory available on the router.

Note Stream Control Transmission Protocol (SCTP) receive windows are scaled at two times the step-size argument value.

Note The actual window size value that is used by the router may be smaller than the configured value because of the available bandwidth.

Examples

The following example shows how to enable window stuffing on the RBSCP tunnel and configure a window size of 2: 

Router(config)# interface tunnel 0

Router(config-if)# tunnel rbscp window_stuff 2

Related Commands

Command
Description

show rbscp

Displays state and statistical information about RBSCP tunnels.


Copyright © 2004 Cisco Systems, Inc. All rights reserved.