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help needed CISCO 3845 vs CISCO 3945

Hi all,

we are planning to buy a couple of routers to migrate our infrastructure to BGP. we were looking at this router:

CISCO 3845
However, we have some concerns about its capabilities and throughput  for BGP.
Currently we have two uplinks to our ISPs (60Mbps each one) and sometimes we increase it to 100Mbps for special weeks during the year.
We will use these routers only for routing, we won't use any other feature like VOICE.  
We are assuming we will use FULL BGP table (we haven't define it yet so I'm thinking worst case scenario) and finally, we'll require 4x1Gig. Ethernet interfaces minimum.

we already did our research and according to this link, the max throughput is 256Mbps : routerperformance.pdf
However, according to Miercom, the real throughput is  45-50Mbps.
Miercom report

Based on the data supplied, and allowing some future growing with the same hardware, do you recommend the 3845 router or can you recommend other that will fit our needs?

What will be the min. Memory required for BGP (full table and partial table)

thank you in advance.
2 Solutions
John MeggersNetwork ArchitectCommented:
If you look carefully at the Miercom results, their throughput figure you quote is with additional security services (zone-based firewall, IDS and VPN) enabled, which you say you're not going to do. So, personally, I wouldn't be concerned about the throughput, I suspect you'll be OK from that standpoint.

I'm a little more concerned about running a full internet table, which last time I looked was around 350k routes.  If you're going to do that I would make sure you have enough memory to handle it.  The 3845 comes standard with 256MB of RAM and maxes out at around 1GB RAM.  I think I'd want at least 512MB if not the full 1GB, but I can't claim any personal experience with what would be the best choice.  You mentioned the 3945, and it comes with 1GB standard, so it may be worth it to purchase the 3945 instead and get the additional performance.  The 3845 has been around for a few years now, so in the long run you will probably be better off with the 3945.

You can also talk to your Cisco SE or partner SE and get their perspective.  The Cisco SE may have access to internal testing results that may help you make a decision.
I share this opinion, the 45Mbps uses all services including paquet fragmentation in case of VPN use (very hungry process).
The 3945 is given for 155Mbps with all services, and this is for approximatly the same price than the 3845, go for this one.
David BangCommented:
If price is the concern, just go with the 3845 and buy 1g flash to replace the old one for better perfomance.
Unless financial is not an issue.
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