AnswerBun.com

Implementation of multi-lane ethernet

Network Engineering Asked by user3563894 on December 8, 2020

In multi-lane ethernet, are the lanes synchronized? i.e., if the symbol of byte 1 of a packet is sent in lane 1, the symbol of byte 2 of a packet is sent in lane 2, then symbol of byte 1 will be received before byte 2?

One Answer

There's no simple answer.

How data is distributed across multiple lanes depends on the exact physical layer variant. With 1000BASE-T, possibly the most popular multi-lane variant, the four five-level symbols transmitted simultaneously form a four-dimensional tuple (4D-PAM5). Each symbol at 125 MBaud effectively transports two MAC bits, resulting in an effective data rate of 250 Mbit/s per pair or 1000 Mbit/s in total.

Effectively, each MAC byte is split into four two-bit groups, encoded and sent simultaneously across the four pairs. See IEEE 802.3 Clause 40 for details.

While that might look like a parallel transmission from a high point of view, it still is serial. The main difference is the common clock for parallel transmission lines (with the inherent clock skew problems) and the separate (embedded) clocks for each serial lane.

Other PHY variants may split data on the bit, nibble or even byte level. There's no general method.

Correct answer by Zac67 on December 8, 2020

Add your own answers!

Related Questions

How to handle multicast address collisions?

2  Asked on September 30, 2021 by youli-luo

       

Configure 2 PPPoE wan trunk port

1  Asked on September 30, 2021 by b4nerj3e

 

What’s the role of the AF entity in LTE network?

2  Asked on September 30, 2021 by amel-benaida

   

Router and switches routing protocol configuration

2  Asked on September 30, 2021 by user10776032

     

How to init connection with a Cisco over serial & minicom?

1  Asked on September 30, 2021 by ymudyruc

   

Do switches allow parallel connections?

1  Asked on September 30, 2021 by ralph-davis

     

intervlan routing with PfSense

1  Asked on September 30, 2021 by bocajnet

       

PAT with multiple VLAN

1  Asked on September 30, 2021 by wahaz

       

CCNA No Longer Required?

1  Asked on February 20, 2021 by jrdvtech

 

BGP unnumbered on P2MP link

1  Asked on January 30, 2021 by eugene-d-gubenkov

         

Minimum frame size in ethernet CSMA/CD

1  Asked on January 27, 2021 by rahul-sharma

   

Signaling vs encoding

5  Asked on January 17, 2021 by user1534664

   

What’s the difference between IKE and ISAKMP?

4  Asked on January 8, 2021 by jeremy-stretch

     

Ask a Question

Get help from others!

© 2022 AnswerBun.com. All rights reserved. Sites we Love: PCI Database, MenuIva, UKBizDB, Menu Kuliner, Sharing RPP