Just another thought...since I know the 831's work for this scenario, I was wondering if there was any downside to using them instead of the 851/871? I've read that the 851's have a limited IOS, is this true?
It seems like the 831's are a tried and tested router...maybe it's best to stick with them??
The 831's will work, but if you reference the link, you'll see they only support 5 VPN tunnels, so your future growth may be limited. They run the same IOS as the 870 series (as well as all the ISRs). If you can afford it, I would lean towards the 870 series. Better performance and there is no downside to the different hardware or IOS.
Just be careful with the 870. Basic configuration comes with 24mb flash and if you want the higher feature IOS you need to get at least 28mb flash. Don't remember what you need for the 15.0 IOS. If you have limited budget, as Collin mentioned, 870 with beefed up flash to support 15.0 IOS would be the way to go. If you have more funds, then I'd recommend either the 880/890 series.
831's can be purchased new for just $60, the 871's are $550
830 is End-of-Sale. There's no such thing as a "new" 830. It must've come from Cisco via an RMA and even that isn't considered new. It's a refurbished unit. Like what Collin said, 870 is alot favourable because of the number of VPN tunnels it can support. Consider future-proofing. If you get an e-bayed 830 but found out down the track that you need to go more then you wind up burning $60 for nothing, right? Another thing ... what SUPPORT can you get for an end-of-sale model? Close-to-nothing. That's my 2-cents worth. Hope this helps.
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...