Juniper Networks JUNOS OS 10.4 - Manual (Page 29)

Related
Documentation
Ethernet Networking •
• Ethernet Terms and Acronyms on page 3
• Networking and Internetworking with Bridges and Routers on page 6
• Networking at Layer 2: Benefits of Ethernet Frames on page 9
• Networking at Layer 2: Challenges of Ethernet MAC Addresses on page 10
• Networking at Layer 2: Forwarding VLAN Tagged Frames on page 11
• Networking at Layer 2: Forwarding Dual-Tagged Frames on page 13
• Networking at Layer 2: Logical Interface Types on page 14
• A Metro Ethernet Network with MX Series Routers on page 15
• Layer 2 Networking Standards on page 17
Networking at Layer 2: Benefits of Ethernet Frames
In spite of the difficulties of using a bridge to perform the network role of a router, many
vendors, customers, and service providers are attracted to the idea of using Ethernet in
as many places of their networks as possible.
The perceived benefits of Ethernet are:
• Most information starts and ends inside Ethernet frames. Today, this applies to data,
as well as voice (for example, VoIP) and video (for example, Web cams).
• Ethernet frames have all the essentials for networking, such as globally unique source
and destination addresses, error control, and so on.
• Ethernet frames can carry any kind of packet. Networking at Layer 2 is protocol
independent (independent of the Layer 3 protocol). Layer 2 networks work for IP
packets and all other Layer 3 protocols.
• More layers added to the Ethernet frame only slow the networking process down
(“nodal processing delay”).
• Adjunct networking features such as class of service (CoS) or multicasting can be
added to Ethernet as readily as IP networks.
If more of the end-to-end transfer of information from a source to a destination can be
done in the form of Ethernet frames, more of the benefits of Ethernet can be realized on
the network. Networking at Layer 2 can be a powerful adjunct to IP networking, but it is
not usually a substitute for IP networking.
9 Copyright © 2013, Juniper Networks, Inc.
Chapter 1: Overview of Ethernet Solutions