Tftp Inspection; Tls Proxy For Encrypted Voice Inspection; Overview - Cisco PIX 500 Series Configuration Manual

TFTP Inspection

100005 1 udp 647 mountd
100005 1 tcp 650 mountd
100005 2 udp 647 mountd
100005 2 tcp 650 mountd
100005 3 udp 647 mountd
100005 3 tcp 650 mountd
In this output, port 647 corresponds to the mountd daemon running over UDP. The mountd process
would more commonly be using port 32780. The mountd process running over TCP uses port 650 in this
example.
TFTP Inspection
TFTP inspection is enabled by default.
TFTP, described in RFC 1350, is a simple protocol to read and write files between a TFTP server and
client.
The security appliance inspects TFTP traffic and dynamically creates connections and translations, if
necessary, to permit file transfer between a TFTP client and server. Specifically, the inspection engine
inspects TFTP read request (RRQ), write request (WRQ), and error notification (ERROR).
A dynamic secondary channel and a PAT translation, if necessary, are allocated on a reception of a valid
read (RRQ) or write (WRQ) request. This secondary channel is subsequently used by TFTP for file
transfer or error notification.
Only the TFTP server can initiate traffic over the secondary channel, and at most one incomplete
secondary channel can exist between the TFTP client and server. An error notification from the server
closes the secondary channel.
TFTP inspection must be enabled if static PAT is used to redirect TFTP traffic.

TLS Proxy for Encrypted Voice Inspection

This section describes TLS proxy for encrypted voice inspection. This section includes the following
topics:
•
•
•
•
•

Overview

With encrypted voice inspection, the security appliance decrypts, inspects and modifies (as needed, for
example, performing NAT fixup), and re-encrypts voice signaling traffic while all of the existing VoIP
inspection functions for Skinny and SIP protocols are preserved. Once voice signaling is decrypted, the
plaintext signaling message is passed to the existing inspection engines.
Cisco Security Appliance Command Line Configuration Guide
25-80
Overview, page 25-80
Maximum TLS Proxy Sessions, page 25-81
Configuring TLS Proxy, page 25-82
Debugging TLS Proxy, page 25-85
CTL Client, page 25-88
Chapter 25 Configuring Application Layer Protocol Inspection
OL-12172-03