Solved: Router throughput good for ADSL2 / 2+

aconticisco · ‎10-12-2013

Found out that the 1721 Router is not suitable due to limitations in its processor and is unable to achieve traffic higher than 6Mbps when switching between the switch wic card and the integrated lan port.

Could you suggest the best next in line router which would be able to support at least 20Mbps internet connection. Planning to connect an external ISP adsl modem/router connected to a router Fast Ethernet port. So router needs to have 2 FE (one for WAN and other for LAN).

Thank You.

Leo Laohoo · ‎10-12-2013

I think a lot of us are familiar with the routerperformance.pdf file. One of the most linked document in Cisco. (Too bad it is no longer be updated.)

The values you are looking are correct. But the values are hyper-/super- exagerated. The values are expressed in one-way traffic (half duplex) and without any encryption. If you want to do internet-only and no encryption/VPN then HALF the value and you'll get traffic expressed in full duplex (or two-way) traffic.

If you want encryption and two-way traffic, take the value and factor (or divide) by FOUR.

Some will argue that encryption doesn't chew up half of the bandwidth and I will agree. The true value is kept close in Cisco so the rule-of-thumb when calculating encryption is factor by half. The real value can sometimes be 40% to 45% so by factoring by half, you get more-than-enough leeway.

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Leo Laohoo · ‎10-12-2013

Try an 890. It has a built-in 8-port switch plus a WAN port.

aconticisco · ‎10-12-2013

was looking at the 2621 so that 1 FE port would be connected to the ISP external ADSL Modem/Router and the other FE to a 2950 switch

Leo Laohoo · ‎10-12-2013

The 2621 is a router OLDER than your current 1721. If you think that your 1721 is unable to push higher than 6 Mbps, do you think an older 2621 can?

aconticisco · ‎10-12-2013

ok thought model numbers are an indication of when they were produced.

Look at this sheet please, is the Fast/CEF Switching Mbps column where I need to focus my attention for throughput ?

http://www.cisco.com/web/partners/downloads/765/tools/quickreference/routerperformance.pdf

Leo Laohoo · ‎10-12-2013

I think a lot of us are familiar with the routerperformance.pdf file. One of the most linked document in Cisco. (Too bad it is no longer be updated.)

The values you are looking are correct. But the values are hyper-/super- exagerated. The values are expressed in one-way traffic (half duplex) and without any encryption. If you want to do internet-only and no encryption/VPN then HALF the value and you'll get traffic expressed in full duplex (or two-way) traffic.

If you want encryption and two-way traffic, take the value and factor (or divide) by FOUR.

Some will argue that encryption doesn't chew up half of the bandwidth and I will agree. The true value is kept close in Cisco so the rule-of-thumb when calculating encryption is factor by half. The real value can sometimes be 40% to 45% so by factoring by half, you get more-than-enough leeway.

aconticisco · ‎10-13-2013

Great therefore the Cisco 2691 seems to be a good match at a budget price while giving a performance of at least 15Mbps. Will go for that one, my intention is to use one FE to connect with ISP ADSL Modem and other FE to cisco Switch with VLANS. Throughput will be much much faster than the 1721. Will enable VPN if possible to allow remote clients to connect it.

Very informative, will allow for some last feedback if required before closing this question.