I'm attempting to set up a Cisco 1921 router running IOS15, and am having trouble with the NAT - it might be that what I am attempting is not possible. If someone can guide me to the right topic, or the area to investigate that would be great. The only traffic going across the router is UDP, and the outside of the network canot be changed. I have two servers on the LAN side 192.168.200.1/24 192.168.200.2/24 and the default gateway on the outside is 10.168.41.56/24 The Router is set up with Inside 192.168.200.254/24 and Outside 10.168.41.50/24 The data transmission is UDP only: From inside to outside From 192.168.200.1:20000 to 10.1.6.x:65535 must look like from 10.168.41.49:65533 to 10.1.6.x:65535 From 192.168.200.2:20000 to 10.1.6.x:65535 must look like from 10.168.41.49:65533 to 10.1.6.x:65535 From outside to inside From 10.1.6.x:65535 to 10.168.41.49:65533 must arrive at both servers looking like from 10.1.6.x:65535 to 192.168.200.1:30000 and 10.1.6.x:65535 to 192.168.200.2:30000 From 10.1.1.x:8601 to 10.168.41.49:8601 must arrive at both servers looking like from 10.1.1.x:8601 to 192.168.200.1:8601 and 10.1.1.x:8601 to 192.168.200.2:8601 My problem is the inside to outside data needs to look like it came from the same IP address and Port Number. As its 1-way data, conceptually there are no problems with this, but I don't seem to be able to implement it as all the static NAT seems to be bidirectional. I cannot type all the rules in as if they are all bidirectional then there are conflicts. Is there an alternative way of doing this? The outside to inside data can be sent to a LAN broadcast address, and this works fine. There is NO other traffic across this router Thanks for your help, Andy ... View more

We've installing a new system for communicating out to 150ish remote sites from a single location. The comms network between them is going to be a single G703/E1 link back to a single location. The connection at the central location is going to be a number of STM-1 aggregated links - E1 out to each site (2Mbps) The operation is a Central Ethernet network performing various processing tasks with data frmo a Railway Control System, and the remote sites contain a very small IP network to display the ifnormation I've been looking at various Cisco products and interface modules, and there are a few which have STM-1 interfaces, however they don't seem to mention it as an aggregation of E1 circuits. The only one I could find was for the 12000 series. Is trhere a more cost effective option? Also, any tips for a basic E1 to Ethernet router for each of the 150 ish remote sites? I'm fine with LAN stuff, and basic routing, this is the first time we've been going over these sorts of networks. We're working out initial cost estimates, and I don't want to spring any suprises. Thanks Andy ... View more

I have a few SRW2008P Linksys/Cisco Small Business switches that are being used within a railway passnger information system. Our assurance engineers would like to know the Mean Time To Fail (MTTF). This information is not in the data sheet. Can anyone assist with this? The warranty is 5 years, which I can use as a basic answer, but would prefer a number in hours - these things for electronic components are typically described as something like > 50,000 hours Many thanks Andy ... View more