ZyXEL Communications IES-1000 11.5Interleave Delay, 11.6ADSL Configured Versus Actual Rate, 11.7ADSL Module Default Settings, 11.5.1Fast Mode, 11.7.1Default Profile Settings

IES-1000 User’s Guide

11.5Interleave Delay

Interleave delay is the wait (in milliseconds) that determines the size of a single block of data to be interleaved (assembled) and then transmitted. Interleave delay is used when transmission error correction (Reed- Solomon) is necessary due to a less than ideal telephone line. The bigger the delay, the bigger the data block size, allowing better error correction to be performed.

Reed-Solomon codes are block-based error correcting codes with a wide range of applications. The Reed-Solomon encoder takes a block of digital data and adds extra "redundant" bits. The Reed-Solomon decoder processes each block and attempts to correct errors and recover the original data.

11.5.1Fast Mode

Fast mode means no interleaving takes place and transmission is faster (a “fast channel”). This would be suitable if you have a good line where little error correction is necessary.

11.6ADSL Configured Versus Actual Rate

You configure the maximum rate of an individual ADSL port by modifying its profile (see the ADSL Edit Profile screen) or assigning the port to a different profile (see the ADSL Edit Port Setup screen). However, due to noise and other factors on the line, the actual rate may not reach the maximum that you specify.

Even though you can specify arbitrary numbers using the ADSL Edit Profile screen, the actual rate is always a multiple of 32 Kbps. If you enter a rate that is not a multiple of 32 Kbps, the actual rate will be the next lower multiple of 32Kbps. For instance, if you specify 60 Kbps for a port, the actual rate for that port will not exceed 32 Kbps, and if you specify 66 Kbps, the actual rate will not be over 64Kbps.

11.7ADSL Module Default Settings

The default profile always exists and all of the ADSL ports use the default profile settings when the AAM-1008 is shipped. The default profile's name is DEFVAL. The default profile’s maximum downstream rate can only be obtained when using the G.dmt standard. Configure a profile with a maximum downstream rate of 1536 Kbps or less for use with G.lite.

11.7.1Default Profile Settings

The following are the settings of the default profile.

-Name: DEFVAL

-Profile Status: Active Downstream ADSL settings:

-Latency Delay: 4ms

-Target Signal/Noise Ratio: 6 db

11-2 ADSL Module Port Setup