A nice simple one for the firewall Gurus out there:
I'm thinking of replacing a tired old Checkpoint firewall cluster with Cisco ASA 5525Xs. I have read the manuals and it looks like this model is SIP aware, but I'd like to hear of anyone's experiences. I have a simple requirement, I'm on a network with Cisco switches/routers, and NEC C3 telephony and I would like to run SIP phones outside the firewall, so SIP awareness is important.
Cisco ASA Firewalls come with an Embedded SIP inspection that will allow you to capture the signaling flow of a SIP session so then the RTP data flow can be dynamically opened while at the same time making sure the data enforce what the RFC states for the SIP protocol.
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...