cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Bookmark
|
Subscribe
|
479
Views
3
Helpful
4
Replies

Cisco Router Throughtput Inquiry

AstralVoyager
Level 1
Level 1

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?

AstralVoyager_0-1740115571130.png

 

1 Accepted Solution

Accepted Solutions

M02@rt37
VIP
VIP

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...

 

Best regards
.ı|ı.ı|ı. If This Helps, Please Rate .ı|ı.ı|ı.

View solution in original post

4 Replies 4

M02@rt37
VIP
VIP

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...

 

Best regards
.ı|ı.ı|ı. If This Helps, Please Rate .ı|ı.ı|ı.

Joseph W. Doherty
Hall of Fame
Hall of Fame

@AstralVoyager wrote:

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

AstralVoyager_0-1740115571130.png


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.


@AstralVoyager wrote:

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

AstralVoyager_0-1740115571130.png


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.

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!

"Downlink 1000Mbps, Uplink typically 30Mbps only. . ."

In that case your aggregate max is 1030, well under the 1673, but, again for PPPoE, fragmentation can potentially cause a huge reduction in IPv4 throughput.  That can often be mostly mitigated by using the IP TCP MSS-ADJUST interface configuration command or by decreasing MTU on your hosts.

Again, for IPv6, MTU shouldn't be an issue.  However, something I forgot to mention, because of IPv6's larger addresses, sometimes forwarding is slower, even much slower, than for IPv4.  Notice in the stats you posted it's explicitly noted it's IPv4 IMIX throughput.

Also, I forgot to mention, any additional "services" (e.g. NAT, ACLs, etc.) can reduce throughput (notice the reduction for IPSec IMIX).

So, given all the forgoing, that model router cannot GUARANTEE it can keep up with your 1030 Mbps.

However, in the real world, often less than maximum bandwidth forwarding is demanded on average, a point of IMIX too.  So, that model will, as M02@rt37 wrote ". . . the C1111X-8P should support your full 1000 Mbps PPPoE broadband with minimal issues." is, I believe, correct; but, understand that statement.

Also when M02@rt37 wrote "However, PPPoE adds some overhead because of encapsulation, which slightly reduces the effective throughput...", is true regarding the bandwidth consumed by it, but if it creates fragmentation, it's a completely different situation.  (That's the reason IPv6 works to make any fragmentation impossible.)

Lastly, M02@rt37 also wrote "However, for absolute peak performance, you may want to test with real-world conditions once set up...".  And, if it's not, you either need to live with the situation or move to a more powerful router.

Am I saying it's BAD to use this model for your case?  Not at all!  If fact even a lessor model might work perfectly for you.  I just want to insure you understand this model might not work well in your case too.