Cisco CSS 11000 Series Content Services Switches

Configuring Wire Speed RealAudio Streaming on the CSS 11000

Document ID: 46223

Updated: Jan 31, 2006



The Cisco CSS series content services switches can recognize TCP and User Datagram Protocol (UDP) flows at Layer 5. The CSS switches switch the flows at wire speed. The switches identify UDP RealAudio flows and considers the flows connected. In addition to the switch performance at wire speed, hardware handles the switch instead of the CPU, as occurs with other switches.



There are no specific requirements for this document.

Components Used

This document is not restricted to specific software and hardware versions.


For more information on document conventions, refer to the Cisco Technical Tips Conventions.


In this section, you are presented with the information to configure the features described in this document.

Note: In order to find additional information on the commands used in this document, use the Command Lookup Tool (registered customers only) .

Network Diagram

This document uses this network setup:



The servers RealAudio1 and RealAudio2 are RealAudio servers. If you initiate multiple flows from multiple clients to overload the switch, you notice that the switch does not collapse under overload conditions. You can use the same technique to improve the performance of FTP sites. Issue the application ftp-control command and set the L3 rule to "tcp" and "port 21".


This document uses this configuration:

!************************* INTERFACE *************************

interface ethernet-12           

!--- This is the uplink to the external network.
!--- All other ports default to VLAN1.

  bridge vlan 2

!************************** CIRCUIT **************************

!Server Side

circuit VLAN1

   ip address


!Router Side

circuit VLAN2

   ip address

!****************SERVICE **********************

service RealAudio1

  ip address


service RealAudio2

  ip address


!**************** OWNER ***********************

!L3 Rule with ACA


    content L3_RealAudio

    vip address

    protocol tcp                

!--- This is the RealAudio inbound setup on TCP port 554.
!--- Handle with these servers.

    port 554                    
    add service RealAudio1      
    add service RealAudio2

    application realaudio-control 

!--- Treat the UDP as a standard flow.


 !*************************** GROUP ***************************

!Source Group provides Inverse NATing.

group 1

  vip address

  add service RealAudio1

  add service RealAudio2



This section provides information you can use to confirm that your configuration works properly.

Stream audio from the servers. Notice that the switch handles the "nonflow-like" RealAudio packets as if the packets are a TCP flow. The switch switches the packets at the lowest layer so there is no performance degradation for use of the UDP traffic.


There is currently no specific troubleshooting information available for this configuration.

Related Information

Updated: Jan 31, 2006
Document ID: 46223