Feedback
|
Table Of Contents
Prerequisites for SIP Bind Features
Restrictions for SIP Bind Features
Information About SIP Bind Features
How to Configure SIP Bind Features
Setting the Bind Command at the Global Level
Setting the Bind Command at the Dial-peer Level
Configuration Examples for SIP Bind Features
Example: Verifying the bind Command
Feature Information for SIP Bind Features
Configuring SIP Bind Features
First Published: October 24, 2001Last Updated: July 21, 2010The SIP Gateway Support for the bind Command feature allows you to configure the source IP address of signaling packets and media packets.
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the "Feature Information for SIP Bind Features" section.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Contents
•
Prerequisites for SIP Bind Features
•
Restrictions for SIP Bind Features
•
Information About SIP Bind Features
•
How to Configure SIP Bind Features
•
Configuration Examples for SIP Bind Features
•
Feature Information for SIP Bind Features
Prerequisites for SIP Bind Features
The following are the prerequisites for this feature:
•
Ensure the gateway has voice functionality that is configurable for Session Initiation Protocol (SIP).
•
Establish a working IP network. For more information about configuring IP, refer to the Cisco IOS IP Addressing Configuration Guide.
•
Configure VoIP. For more information about configuring VoIP, refer to the Cisco IOS Voice Command Reference.
Restrictions for SIP Bind Features
Although the bind all command is an accepted configuration, it does not appear in show running-config command output. Because the bind all command is equivalent to issuing the commands bind source and bind media, those are the commands that appear in the show running-config command output.
Information About SIP Bind Features
When you configure SIP on a router, the ports on all its interfaces are open by default. This makes the router vulnerable to malicious attackers who can execute toll fraud across the gateway if the router has a public IP address and a public switched telephone network (PSTN) connection. To eliminate the threat, you should bind an interface to an IP address so that only those ports are open to the outside world. In addition, you should protect any public or untrusted interface by configuring a firewall or an access control list (ACL) to prevent unwanted traffic from traversing the router.
Benefits of SIP Bind Features
The benefits of SIP Bind feature is as follows:
•
SIP signaling and media paths can advertise the same source IP address on the gateway for certain applications, even if the paths used different addresses to reach the source. This eliminates confusion for firewall applications that may have taken action on source address packets before the use of binding.
•
Firewalls filter messages based on variables such as the message source, the target address, and available ports. Normally a firewall opens only certain addresses or port combination to the outside world and those addresses can change dynamically. Because VoIP technology requires the use of more than one address or port combination, the bind command adds flexibility by assigning a gateway to a specific interface (and therefore the associated address) for the signaling or media application.
•
You can obtain a predefined and separate interface for both signaling and media traffic. Once a bind command is in effect, the interface it limits is bound solely to that purpose. Administrators can therefore dictate the use of one network to transport the signaling and another network to transport the media. The benefits of administrator control are:
–
Administrators know the traffic that runs on specific networks, thereby making debugging easier.
–
Administrators know the capacity of the network and the target traffic, thereby making engineering and planning easier.
–
Traffic is controlled, allowing Qualtiy of Service (QoS) to be monitored.
•
The bind media command relaxes the constraints imposed by the bind control and bind all commands, which cannot be set during an active call. The bind media command works with active calls.
To configure SIP Gateway Support for the bind Command, you should understand the following concepts:
•
Voice Media Stream Processing
Source Address
In early releases of Cisco IOS software with SIP functionality, the source address of a packet going out of the gateway was never deterministic. That is, the session protocols and VoIP layers always depended on the IP layer to give the best local address. The best local address was then used as the source address (the address showing where the SIP request came from) for signaling and media packets. Using this nondeterministic address occasionally caused confusion for firewall applications, because a firewall could not be configured with an exact address and would take action on several different source address packets.
However, the bind command allows you to configure the source IP address of signaling and media packets to a specific interface's IP address. Thus, the address that goes out on the packet is bound to the IP address of the interface specified with the bind command. Packets that are not destined to the bound address are discarded.
When you do not want to specify a bind address or if the interface is down, the IP layer still provides the best local address.
The Support Ability to Configure Source IP Address for Signaling and Media per SIP Trunk feature extends the global bind functionality to support the SIP signaling Transport Layer Socket (TLS) with UDP and TCP. The source address at the dial peer is the source address in all the signaling and media packets between the gateway and the remote SIP entity for calls using the dial-peer. Multiple SIP listen sockets with specific source address handle the incoming SIP traffic from each selected SIP entity. The order of preference for retrieving the SIP signalling and media source address for inbound and outbound calls is as follows:
•
Bind configuration at dial peer level
•
Bind configuration at global level
•
Best local IP address to reach the destination
Table 1 describes the state of the system when the bind command is applied in the global or dial peer level:
The bind command performs different functions based on the state of the interface (see Table 2).
The bind command applied at the dial peer level can be modified only in the following situations:
•
Dial peer bind is disabled in the supported IOS configuration options.
•
Dial peer bind is removed when the bound interface is removed.
•
Dial peer bind is removed when the dial peer is removed.
Voice Media Stream Processing
The SIP Gateway Support Enhancements to the bind Command feature extends the capabilities of the bind command by supporting a deterministic network interface for the voice media stream. Before the voice media stream addition, the bind command supported a deterministic network interface for control (signaling) traffic or all traffic. With the SIP Gateway Support Enhancements to the bind Command feature a finer granularity of control is achieved on the network interfaces used for voice traffic.
If multiple bind commands are issued in sequence—that is, if one bind command is configured and then another bind command is configured—a set interaction happens between the commands. Table 3 describes the expected command behavior.
The bind all and bind control commands perform different functions based on the state of the interface. Table 4 describes the actions performed based on the interface state.
Note
The bind all command only applies to global level, whereas the bind control and bind media command apply to global and dial peer. Table 4 applies to bind media only if the media interface is the same as the bind control interface. If the two interfaces are different, media behavior is independent of the interface state.
How to Configure SIP Bind Features
This section contains the following procedures:
•
Setting the Bind Command at the Global Level (required)
•
Setting the Bind Command at the Dial-peer Level (optional)
•
Monitoring the Bind Command (optional)
Setting the Bind Command at the Global Level
To configure the bind command to an interface at the global level, perform the following steps.
Note
The bind media command applies to specific interfaces.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
interface type/number
4.
ip address ip-address mask [secondary]
5.
exit
6.
voice service voip
7.
sip
8.
bind {control | media | all} source-interface interface-id [ipv6-address ipv6-address]
9.
exit
DETAILED STEPS
Setting the Bind Command at the Dial-peer Level
To configure the bind command on SIP for a VoIP dial-peer, perform the following steps.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
interface type/number
4.
ip address ip-address mask [secondary]
5.
exit
6.
dial-peer voice tag voip
7.
session protocol sipv2
8.
voice-class sip bind {control | media} source interface interface-id [ipv6-address ipv6-address]
9.
exit
DETAILED STEPS
Troubleshooting Tips
For troubleshooting tips and a list of important debug commands, see Verifying and Troubleshooting SIP Features.
Monitoring the Bind Command
To monitor the bind command, perform the following steps.
SUMMARY STEPS
1.
show ip sockets
2.
show sip-ua status
3.
show sip-ua connections {tcp [tls] | udp} {brief | detail}
4.
show dial-peer voice
DETAILED STEPS
Step 1
show ip sockets
Use this command to display IP socket information and indicate whether the bind address of the receiving gateway is set.
The following sample output indicates that the bind address of the receiving gateway is set:
Router# show ip socketsProto Remote Port Local Port In Out Stat TTY OutputIF
17 0.0.0.0 0 --any-- 2517 0 0 9 0
17 --listen-- 172.18.192.204 1698 0 0 1 0
17 0.0.0.0 0 172.18.192.204 67 0 0 489 0
17 0.0.0.0 0 172.18.192.204 5060 0 0 A1 0
Step 2
show sip-ua status
Use this command to display SIP user-agent status and indicate whether bind is enabled.
The following sample output indicates that signaling is disabled and media on 172.18.192.204 is enabled:
Router# show sip-ua statusSIP User Agent StatusSIP User Agent for UDP : ENABLEDSIP User Agent for TCP : ENABLEDSIP User Agent for TLS over TCP : ENABLEDSIP User Agent bind status(signaling): DISABLEDSIP User Agent bind status(media): ENABLED 172.18.192.204SIP early-media for 180 responses with SDP: ENABLEDSIP max-forwards : 70SIP DNS SRV version: 2 (rfc 2782)NAT Settings for the SIP-UARole in SDP: NONECheck media source packets: DISABLEDMaximum duration for a telephone-event in NOTIFYs: 2000 msSIP support for ISDN SUSPEND/RESUME: ENABLEDRedirection (3xx) message handling: ENABLEDReason Header will override Response/Request Codes: DISABLEDOut-of-dialog Refer: DISABLEDPresence support is DISABLEDprotocol mode is ipv4SDP application configuration:Version line (v=) requiredOwner line (o=) requiredTimespec line (t=) requiredMedia supported: audio video imageNetwork types supported: INAddress types supported: IP4 IP6Transport types supported: RTP/AVP udptlStep 3
show sip-ua connections {tcp [tls] | udp} {brief | detail}
Use this command to display the connection details for the UDP transport protocol. The command output looks identical for TCP and TLS.
Router# show sip-ua connections udp detailTotal active connections : 0No. of send failures : 0No. of remote closures : 0No. of conn. failures : 0No. of inactive conn. ageouts : 10---------Printing Detailed Connection Report---------Note:** Tuples with no matching socket entry- Do 'clear sip <tcp[tls]/udp> conn t ipv4:<addr>:<port>'to overcome this error condition++ Tuples with mismatched address/port entry- Do 'clear sip <tcp[tls]/udp> conn t ipv4:<addr>:<port> id <connid>'to overcome this error conditionNo Active Connections Found-------------- SIP Transport Layer Listen Sockets ---------------Conn-Id Local-Address=========== =============================2 [9.42.28.29]:5060Step 4
show dial-peer voice
Use this command, for each dial peer configured, to verify that the dial-peer configuration is correct. The following is sample output from this command for a VoIP dial peer:
Router# show dial-peer voice 101VoiceOverIpPeer1234peer type = voice, system default peer = FALSE, information type = voice,description = `',tag = 1234, destination-pattern = `',voice reg type = 0, corresponding tag = 0,allow watch = FALSEanswer-address = `', preference=0,CLID Restriction = NoneCLID Network Number = `'CLID Second Number sentCLID Override RDNIS = disabled,rtp-ssrc mux = systemsource carrier-id = `', target carrier-id = `',source trunk-group-label = `', target trunk-group-label = `',numbering Type = `unknown'group = 1234, Admin state is up, Operation state is down,incoming called-number = `', connections/maximum = 0/unlimited,DTMF Relay = disabled,modem transport = system,URI classes:Incoming (Request) =Incoming (Via) =Incoming (To) =Incoming (From) =Destination =huntstop = disabled,in bound application associated: 'DEFAULT'out bound application associated: ''dnis-map =permission :bothincoming COR list:maximum capabilityoutgoing COR list:minimum requirementoutgoing LPCOR:Translation profile (Incoming):Translation profile (Outgoing):incoming call blocking:translation-profile = `'disconnect-cause = `no-service'advertise 0x40 capacity_update_timer 25 addrFamily 4 oldAddrFamily 4mailbox selection policy: nonetype = voip, session-target = `',technology prefix:settle-call = disabledip media DSCP = ef, ip media rsvp-pass DSCP = efip media rsvp-fail DSCP = ef, ip signaling DSCP = af31,ip video rsvp-none DSCP = af41,ip video rsvp-pass DSCP = af41ip video rsvp-fail DSCP = af41,ip defending Priority = 0, ip preemption priority = 0ip policy locator voice:ip policy locator video:UDP checksum = disabled,session-protocol = sipv2, session-transport = system,req-qos = best-effort, acc-qos = best-effort,req-qos video = best-effort, acc-qos video = best-effort,req-qos audio def bandwidth = 64, req-qos audio max bandwidth = 0,req-qos video def bandwidth = 384, req-qos video max bandwidth = 0,RTP dynamic payload type values: NTE = 101Cisco: NSE=100, fax=96, fax-ack=97, dtmf=121, fax-relay=122CAS=123, TTY=119, ClearChan=125, PCM switch over u-law=0,A-law=8, GSMAMR-NB=117 iLBC=116, AAC-ld=114, iSAC=124lmr_tone=0, nte_tone=0h263+=118, h264=119G726r16 using static payloadG726r24 using static payloadRTP comfort noise payload type = 19fax rate = voice, payload size = 20 bytesfax protocol = systemfax-relay ecm enableFax Relay ans enabledFax Relay SG3-to-G3 Enabled (by system configuration)fax NSF = 0xAD0051 (default)codec = g729r8, payload size = 20 bytes,video codec = Nonevoice class codec = `'voice class sip session refresh systemvoice class sip rsvp-fail-policy voice post-alert mandatory keep-alive interval 30voice class sip rsvp-fail-policy voice post-alert optional keep-alive interval 30voice class sip rsvp-fail-policy video post-alert mandatory keep-alive interval 30voice class sip rsvp-fail-policy video post-alert optional keep-alive interval 30text relay = disabledMedia Setting = forking (disabled) flow-through (global)Expect factor = 10, Icpif = 20,Playout Mode is set to adaptive,Initial 60 ms, Max 1000 msPlayout-delay Minimum mode is set to default, value 40 msFax nominal 300 msMax Redirects = 1, signaling-type = cas,VAD = enabled, Poor QOV Trap = disabled,Source Interface = NONEvoice class sip url = system,voice class sip tel-config url = system,voice class sip rel1xx = system,voice class sip anat = system,voice class sip outbound-proxy = "system",voice class sip associate registered-number =system,voice class sip asserted-id system,voice class sip privacy systemvoice class sip e911 = system,voice class sip history-info = system,voice class sip reset timer expires 183 = system,voice class sip pass-thru headers = system,voice class sip pass-thru content unsupp = system,voice class sip pass-thru content sdp = system,voice class sip copy-list = system,voice class sip g729 annexb-all = system,voice class sip early-offer forced = system,voice class sip negotiate cisco = system,voice class sip block 180 = system,voice class sip block 183 = system,voice class sip block 181 = system,voice class sip preloaded-route = system,voice class sip random-contact = system,voice class sip random-request-uri validate = system,voice class sip call-route p-called-party-id = system,voice class sip call-route history-info = system,voice class sip privacy-policy send-always = system,voice class sip privacy-policy passthru = system,voice class sip privacy-policy strip history-info = system,voice class sip privacy-policy strip diversion = system,voice class sip map resp-code 181 = system,voice class sip bind control = enabled, 9.42.28.29,voice class sip bind media = enabled, 9.42.28.29,voice class sip bandwidth audio = system,voice class sip bandwidth video = system,voice class sip encap clear-channel = system,voice class sip error-code-override options-keepalive failure = system,voice class sip calltype-video = falsevoice class sip registration passthrough = Systemvoice class sip authenticate redirecting-number = system,redirect ip2ip = disabledlocal peer = falseprobe disabled,Secure RTP: system (use the global setting)voice class perm tag = `'Time elapsed since last clearing of voice call statistics neverConnect Time = 0, Charged Units = 0,Successful Calls = 0, Failed Calls = 0, Incomplete Calls = 0Accepted Calls = 0, Refused Calls = 0,Last Disconnect Cause is "",Last Disconnect Text is "",Last Setup Time = 0.Last Disconnect Time = 0.
Note
If the bind address is not configured at the dial-peer, the output of the show dial-peer voice command remains the same except for the values of the voice class sip bind control and voice class sip bind media, which display "system", indicating that the bind is configured at the global level.
Troubleshooting Tips
For troubleshooting tips and a list of important debug commands, see Verifying and Troubleshooting SIP Features.
Configuration Examples for SIP Bind Features
This section provides the following configuration examples:
•
Example: Verifying the bind Command
Example: Verifying the bind Command
This sample output shows that bind is enabled on router 172.18.192.204:
Router# show running-configBuilding configuration...Current configuration : 2791 bytes!version 12.2service configno service single-slot-reload-enableno service padservice timestamps debug uptimeservice timestamps log uptimeno service password-encryptionservice internalservice udp-small-servers!ip subnet-zeroip ftp source-interface Ethernet0!voice service voipsipbind control source-interface FastEthernet0!interface FastEthernet0ip address 172.18.192.204 255.255.255.0duplex autospeed autofair-queue 64 256 1000ip rsvp bandwidth 75000 100!voice-port 1/1/1no supervisory disconnect lcfo!dial-peer voice 1 potsapplication sessiondestination-pattern 5550111port 1/1/1!dial-peer voice 29 voipapplication sessiondestination-pattern 5550133session protocol sipv2session target ipv4:172.18.200.33codec g711ulaw!gateway!line con 0line aux 0line vty 0 4login!endAdditional References
Related Documents
Standards
Standard TitleNo new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.
—
MIBs
MIB MIBs LinkCISCO-SIP-UA-MIB
To locate and download MIBs for selected platforms, Cisco software releases, and feature sets, use Cisco MIB Locator found at the following URL:
RFCs
Technical Assistance
Feature Information for SIP Bind Features
Table 5 lists the features in this module and provides links to specific configuration information.
Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Note
Table 5 lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Table 5 Feature Information for SIP Bind Features
Feature Name Releases Feature InformationSIP Gateway Support for the bind Command
12.2(2)XB
12.2(2)XB2
12.2(8)T
12.2(11)T
12.3(4)TThe SIP Gateway Support for the bind command feature allows you to configure the source IP address of signaling packets and media packets.
In 12.2(2)XB, this feature was introduced.
In 12.3(4)T, this feature was expanded to provide the flexibility to specify different source interfaces for signaling and media, and allow network administrators a finer granularity of control on the network interfaces used for voice traffic.
The following sections provide information about this feature:
•
Information About SIP Bind Features
•
How to Configure SIP Bind Features
The following commands were introduced or modified: bind, show dial-peer voice, show ip sockets, show sip-ua connections, show sip-ua status, voice-class sip bind.
Support Ability to Configure Source IP Address for Signaling and Media per SIP Trunk
15.1(2)T
This feature allows you to configure a separate source IP address per SIP trunk. This source IP address is embedded in all SIP signaling and media packets that traverse the SIP trunk. This feature enables service providers for better profiling and billing policies. It also enables greater security for enterprises by the use of distinct IP addresses within and outside the enterprise domain.
The following section provides information about this feature:
•
Setting the Bind Command at the Dial-peer Level
The following command was introduced or modified: voice-class sip bind.
Cisco and the Cisco Logo are trademarks of Cisco Systems, Inc. and/or its affiliates in the U.S. and other countries. A listing of Cisco's trademarks can be found at www.cisco.com/go/trademarks. Third party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1005R)
Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.
© 2001-2010 Cisco Systems, Inc. All rights reserved.
Feedback