TMS zl Management and Configuration Guide ST.1.0.090213

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Firewall
Application-Level Gateways
msn
The MSN ALG supports the following functionalities of Microsoft Instant
Messenger 7.0:
■ instant messaging (chat)
■ file transfer
■ voice conversation
■ video conversation (present in Windows XP)
It opens data associations to allow the data connections to pass through, based
on information that is extracted from the payloads that contain the above
strings, translates the IP address and port information according to NAT
policies, and interprets the following strings that pass through the control-
connection payloads:
•INVITE
• ACCEPT
• APPLICATION TYPE
– FILE TRANSFER
– VOICE CONVERSATION
• APPLICATION COOKIE
netbios
Network Basic Input/Output System (NetBIOS) is a service that is available
in the Windows network environment that allows multiple devices on a LAN
to share resources with each other. The NetBIOS service permits a device to
view all of the other devices on the network, map network drives, share printer
resources, and so on.
The NetBIOS ALG
■ examines payloads and opens the necessary associations.
■ translates the IP address and port information according to NAT policies.
■ blocks the WinNuke attack.
nntp
The NNTP ALG interprets the GROUP command of the NNTP packets, extracts
the group name and allows or denies the request for that group name based
on the configuration by the NNTP administrator.