LAG is commonly used in Ethernet transport, as it provides a relatively transparent path combining multiple smaller links. This allows the engineers to scale link capacity gradually, as well as manage the level of redundancy in the link path.

The LAG terminates on LAG ports in equipment at each end of the LAG, these ports being virtual ports, grouping multiple physical ports on each device. Thus, all individual paths grouped by the LAG terminate at ports on the same pair of devices.

Though LAG is a term most commonly applied in Ethernet transport, the same modelling can apply to DSL and other technologies.

 

In ConnectMaster, LAG is represented by a new Transport Container (TC) type called “Link Aggregation”. This TC operates in a similar way to a “concatenation” TC, in that it groups multiple individual paths to a single aggregated link. These individual paths are represented by a new TC type called “LAG path”.

 

The Link Aggregation TC has the following behaviours / constraints:

•It is a TC in the category “Ethernet“;

•Can only group paths in the category “Ethernet”. When adding a TC to the LAG TC that has an Ethernet type other than “LAG Path”, e.g. “Utilisable Container”, the type of that TC is automatically updated to be “LAG Path”;

•Can terminate only on Virtual Ports of type ‘Virtual Grouping Port’;

•Can define each grouped LAG Path TC as worker or protection;

•Capacity is calculated as the sum of the worker TC paths.

 

The LAG Path TC has the following behaviours / constraints:

•It is a TC in the category “Ethernet”;

•Not possible to route a TC directly over a LAG Path. It must first be grouped by a Link Aggregation TC, then the Link Aggregation TC can be used for routing.

•Can terminate at physical ports (outer ports and inner ports);

•Can only be included in a Link Aggregation TC if it terminates at the same pair of devices as the Link Aggregation TC.