Protocols and Applications

Overview

Possible literal values are ahp, eigrp, esp, gre, icmp, igmp, igrp, ip, ipinip, ipsec, nos, ospf, pcp, snp, tcp, and udp. You can also specify any protocol by number. The esp and ah protocols only work in conjunction with Private Link.

Cisco firewalls do not pass multicast packets. Many routing protocols use multicast packets to transmit their data. If you need to send routing protocols across the firewall, configure the routers with the Cisco IOS software neighbor command. We consider it inherently dangerous to send routing protocols across the firewall. If the routes on the unprotected interface are corrupted, the routes transmitted to the protected side of the firewall will pollute routers there as well.

Literal Value Description
ah 51 Authentication Header for IPv6, RFC 1826
eigrp 88 Enhanced Interior Gateway Routing Protocol
esp 50 Encapsulated Security Payload for IPv6, RFC 1827
gre 47 General Routing Encapsulation
icmp 1 Internet Control Message Protocol, RFC 792
igmp 2 Internet Group Management Protocol, RFC 1112
igrp 9 Interior Gateway Routing Protocol
ip 0 Internet Protocol
ipinip 4 IP-in-IP encapsulation
nos 94 Network Operating System (Novell's NetWare)
ospf 89 Open Shortest Path First routing protocol, RFC 1247
pcp 108 Payload Compression Protocol
snp 109 Sitara Networks Protocol
tcp 6 Transmission Control Protocol, RFC 793
udp 17 User Datagram Protocol, RFC 768

Protocol numbers can be viewed online at the IANA website:

www.iana.org/assignments/protocol-numbers

 

Supported Multimedia Applications

The firewall supports the following multimedia and video conferencing applications:

  1. CUseeMe Networks CU-SeeMe
  2. CUseeMe Networks CU-SeeMe Pro
  3. CUseeMe Networks MeetingPoint
  4. Intel Internet Video Phone
  5. Microsoft NetMeeting
  6. Microsoft NetShow
  7. NetMeeting
  8. RealNetworks RealAudio and RealVideo
  9. VDOnet VDOLive
  10. VocalTec Internet Phone
  11. VXtreme WebTheater
  12. Xing StreamWorks

Supported Protocols and Applications

The firewall supports the following TCP/IP protocols and applications:

  1. Address Resolution Protocol (ARP)
  2. Archie
  3. Berkeley Standard Distribution (BSD)-rcmds
  4. Bootstrap Protocol (BOOTP)
  5. Domain Name System (DNS)
  6. File Transfer Protocol (FTP)
  7. Generic Route Encapsulation (GRE)
  8. Gopher
  9. HyperText Transport Protocol (HTTP)
  10. Internet Control Message Protocol (ICMP)
  11. Internet Protocol (IP)
  12. NetBIOS over IP (Microsoft Networking)
  13. Point-to-Point Tunneling Protocol (PPTP)
  14. Simple Network Management Protocol (SNMP)
  15. Sitara Networks Protocol (SNP)
  16. SQL*Net (Oracle client/server protocol)
  17. Sun Remote Procedure Call (RPC) services, including Network File System (NFS)
  18. Telnet
  19. Transmission Control Protocol (TCP)
  20. Trivial File Transfer Protocol (TFTP)
  21. User Datagram Protocol (UDP)