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Cisco 877w WiFi Speed issue


Hello all,


I have an issue with a 877W Router, while the ISP provides me with a 50 Mbps Internet Feed my download speed over wifi is limited to 20 Mbps. 


Attached there's a sh run of the device. Do you have any ideas?




8 Replies 8

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You can do couple of tests to identify what is wrong.


1. Connect PC to Ethernet port and test are you getting correct speed.

2. then compare the speed with Wifi 

3. when you testing, are you the only user connect to Wifi (or any other devices using)

4. what is the device you using for testing, what wireless nic card and and have correct drivers installed.


since it is various aspect, you can only do test and come to conclusion what is wrong. at this stage we can not say where to problem resides.




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Hello balaji.bandi,

1) I connected my PC to the Ethernet ports of the Router and i am getting correct speed. (Almost 50 bps)
3) I'm the only one connected to the WiFi
4) I tested with several devices such as PCs, Laptops, Mobile Phones and i got the same output. (Around 20 Mbps)

Leo Laohoo
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870 routers were not designed to support 50 Mbps.
870 can handle up to 12.80 Mbps in half duplex, meaning 12.80 Mbps in a single direction.

@Leo Laohoo Good catch, missed device capacity. 


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Hello Leo Laohoo,

Just saw from the datasheet of Cisco the Data Rates Supported for the WiFi: 1, 2, 5.5, 6, 9, 11, 12, 18, 24, 36, 48, and 54 Mbps.

Let me mention that i use this router only as an Access Point, as a router i use the one provided by my ISP,

I am very familiar with the 877W because I had it before. It will not support >15 Mbps.
Wireless is only 2.4 Ghz only.


It is a marketing-speak trick of adding input rate and output rate to get a "total capacity" which sounds more impressive on the data sheet for a device.

If you want to archive the same you can but there will be a lot of tricks.

Try to implement below things and I hope you will get nearby speed to datasheet:


1. Disable all Security and encryption on the Wireless. 

2. There will be no other wireless interference. No other things as oven etc. Only one client will be on the wifi.

3. The client must be optimized for the tested channel.

4. If you are performing the speed test on LAN then the remote client must be connected on Cable. 

5. There will no load on the device and no NATing, No firewall etc.

And so many things are there to perform a DATA sheet test.



Deepak Kumar 

Deepak Kumar,
Don't forget to vote and accept the solution if this comment will help you!

Hello !


Actually i found the above explanation from


802.11g - 802.11 WLAN (wireless LAN) extenson that provides for up to 54 MBps raw data rate (24 Mbps useful throughput) in the 2.4 GHz band.


Thank you all for your time!


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