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New Member

My link is too slow

Hi all,

Please I have connection to the Internet using a VSAT on DVB platform. I use a 1700 series router to link my LAN with the Internet. A Satellite MODEM provides the serial link. I recently noticed that my link is very slow. When I did a Show interfaces on the router, I noticed that the input part of the serial0 reports many input errors, with VERY HIGH CRC, frame and abort values. The output however shows 0,0,0,0 on output, CRC, frame and abort. What is happening and how can I solve this problem?

Kindly help.

A. I. Chafe

New Member

Re: My link is too slow

CRC errors also called alignment errors are most of the time caused by the wrong duplex setting, improper cable, MAC layer packet formation .CRC errors typically indicates noise, gain hits or transmission problem on the data link. Check cable, full/halfduplex setting, faulty driver, NIC. I hope this helps.Good luck

New Member

Re: My link is too slow

Perform a baseband or I.F. loop at your satellite modem, clear the counters on your serial interface and see if you're still taking input errors. If you ARE, start working back from the modem. Check your cabling and any devices between your router and modem. If you are NOT taking errors in that loopback, check your satellite link and ensure you have a good Eb/No and BER.

As it is, satellite links are inherently slower than terrestrial links due to response time over the satellite (average of about 550 ms). Unless you have a device which will increase your throughput over the satellite, your link will be appear to be slower.