A multilayer switch (MLS) is a computer networking device, that switches on OSI layer 2 like an ordinary network switch - and provides extra functions on higher OSI layers.

Table of contents
1 MultiLayer Switch (MLS) - OSI layer 3 and/or 4
2 Layer 7 switch, web-switch, content-switch
3 External addresses

MultiLayer Switch (MLS) - OSI layer 3 and/or 4

A Multilayer Switch (MLS) can prioritize packets by the 6 bits in IP DSCP (differentiated services CodePoint). These 6 bits were used in the "old days" for Type of Service (ToS).

The following 4 mappings are normally available in a MLS:

Many MLS implements QoS differentiated services and/or integrated services in hardware.

Some MLS are also able to route between VLAN and/or portss like a common router. The routing are normally as quick as switching (with wirespeed).

Layer 7 switch, web-switch, content-switch

Some switches can use up to OSI layer 7 packet information, they are called layer 7 switches, content-switch or web-switch.

Some of the applications areas are load-balancing among HTTP, HTTPS and/or VPN servers. Load-balancing can be made by using NAT. Some of the layer 7 switches can NAT at wirespeed.


Sources/references

External addresses