Cisco Router Throughtput Inquiry

[AstralVoyager]

Hi guys! I want to purchase a used C1111X-8P router as my home PPPoE router (don't ask me why lol just because I like Cisco products)

And I have a small question about this IPv4 forwarding throughtput (IMIX). Does it mean that it will handle 1673Mbps PPPoE broadband? Mine is 1000Mbps, so I think this router can make my broadband work in full speed right?

[M02@rt37 · Accepted solution]

Hello @AstralVoyager 

The IPv4 forwarding throughput of 1673 Mbps represents the router’s bidirectional forwarding performance when handling a typical mix of internet traffic. However, PPPoE adds some overhead because of encapsulation, which slightly reduces the effective throughput...

For a 1000 Mbps PPPoE connection, the C1111X-8P should handle it well, but take care, there are some factors to consider:

First, since PPPoE requires additional processing, the actual throughput may be slightly lower than 1673 Mbps.

Next, if your ISP uses PPPoE with additional features (like QoS or deep packet inspection), the router’s CPU usage could increase, potentially impacting performance.

Finally, the 1673 Mbps figure is based on a realistic traffic mix, not just raw packets-per-second performance. If you were pushing purely large packets (which is ideal for speed tests), it might perform even better.

So, yes, the C1111X-8P should support your full 1000 Mbps PPPoE broadband with minimal issues. However, for absolute peak performance, you may want to test with real-world conditions once set up...

[Joseph W. Doherty]

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@AstralVoyager wrote:

And I have a small question about this IPv4 forwarding throughtput (IMIX). Does it mean that it will handle 1673Mbps PPPoE broadband?

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Possibly not.

PPPoE is a wildcard, in its potential impact, as if can often lead to IPv4 packet fragmentation which, depending on the platform can introduce a significant to huge negative throughput impact.  That's something deserving of its own benchmark, which I don't think you're likely to find one published.

For IPv4, there are things you can do to mitigate or totally avoid fragmentation.

For IPv6, if I understand it correctly, PMTUD is required, so I shouldn't happen.

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@AstralVoyager wrote:

Mine is 1000Mbps, so I think this router can make my broadband work in full speed right?

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No, for IMIX traffic that matches the benchmark traffic, assuming you have gig both up and down, you would need a rating of 2 Gbps.

[AstralVoyager]

Yes bro thank you for your reply.

I am in China and our Home broadband has some limit. Downlink 1000Mbps, Uplink typically 30Mbps only, for avoiding build Internet facing server on our own. So I think this model can fulfill my need.

Thanks again!