One of the settings my provider gave me for my T1 line is crc 16. I'm using cisco 1721 w/t1 card. I've not been able to find much information on this setting or a command for it in the router. Is crc 16 a default setting for these older routers?
This is a default command to set a 16 bit CRC check on the data traversing the T-1 interface. Whether you set it or not it is configured on the interface.
quote:CRC is an error-checking technique that uses a calculated numeric value to detect errors in transmitted data. The designators 16 and 32 indicate the length (in bits) of the frame check sequence (FCS). A CRC of 32 bits provides more powerful error detection, but adds overhead. Both the sender and receiver must use the same setting.
CRC-16, the most widely used CRC throughout the United States and Europe, is used extensively with WANs. CRC-32 is specified by IEEE 802 and as an option by some point-to-point transmission standards. It is often used on Switched Multimegabit Data Service (SMDS) networks and LANs.