NAT Traffic Types

NAT Traffic Types
NAT supports many traffic types. The BSCI exam may include questions on both the supported
and unsupported traffic types. The following two sections take a look at these traffic types.
Supported Traffic Types
NAT supports the following traffic types:

TCP traffic that does not carry source and destination IP addresses inside the application
stream

UDP traffic that does not carry source and destination IP addresses inside the application
stream

Hypertext Transfer Protocol (HTTP)

Trivial File Transfer Protocol (TFTP)

File Transfer Protocol (FTP
PORT
and
PASV
command)

Archie, which provides lists of anonymous FTP archives

Finger, a tool that determines whether a person has an account on a particular computer
82
Chapter 3 
Network Address Translation

Network Time Protocol (NTP)

Network File System (NFS)

Many of the r* Unix utilities (rlogin, rsh, rcp)

Internet Control Message Protocol (ICMP)

NetBIOS over TCP (datagram, name, and session services)

Progressive Networks’ RealAudio

White Pines’ CuSeeMe

Xing Technologies’ StreamWorks

DNS A and PTR queries

H.323 (IOS releases 12.0(1)/12.0(1)T or later)

Session Initiation Protocol (SIP)

NetMeeting (IOS releases 12.0(1)/12.0(1)T or later)

VDOLive (IOS releases 11.3(4)/11.3(4)T or later)

Vxtreme (IOS releases 11.2(4)/11.3(4)T or later)
 IP Multicast—source address translation only (IOS releases 12.0(1)T or later)
 PPTP support with Port Address Translation (PAT) (IOS release 12.1(2)T or later)
 Skinny Client Protocol, IP Phone to Cisco CallManager (IOS release 12.1(5)T or later)