# multilayer switch

> Network switch providing functionality above the data link layer

**Wikidata**: [Q264071](https://www.wikidata.org/wiki/Q264071)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Multilayer_switch)  
**Source**: https://4ort.xyz/entity/multilayer-switch

## Summary
A multilayer switch is a network switch that provides functionality above the data link layer (Layer 2) of the OSI model. Unlike standard switches, it can operate at the network layer and often the transport layer, making it a critical component of Internet infrastructure.

## Key Facts
*   **Class:** Subclass of `network switch`.
*   **Primary Function:** Provides network functionality above the data link layer.
*   **OSI Model Layers:** Operates at the data link layer and network layer; often extends to the transport layer.
*   **UNSPSC Code:** 43222621.
*   **Wikipedia Presence:** Available in 10 languages, including English, Arabic, Chinese, and Polish.
*   **Alternative IDs:** Freebase ID `/m/01j54j`; KBpedia ID `ContentSwitch`.
*   **Academic Trace:** Microsoft Academic ID 52761205 (service discontinued).

## FAQs
### Q: What distinguishes a multilayer switch from a standard network switch?
A: While a standard network switch operates primarily at the data link layer (Layer 2), a multilayer switch provides functionality above this layer, specifically at the network layer (Layer 3) and often the transport layer (Layer 4).

### Q: At which layers of the OSI model does a multilayer switch operate?
A: A multilayer switch operates at the data link layer and the network layer. It is also frequently cited as providing functionality at the transport layer.

### Q: What role does a multilayer switch play in Internet infrastructure?
A: As a subclass of the network switch—a main component of computer networks—a multilayer switch uses packet switching to forward data, contributing to the efficiency and structure of the Internet infrastructure.

## Why It Matters
The multilayer switch represents an evolution in networking hardware, bridging the gap between basic data link layer switching and higher-level routing functionalities. By operating above the data link layer, specifically at the network and often transport layers, these devices allow for more intelligent data management and traffic prioritization than a standard switch.

This capability is vital for modern network infrastructure. As a specialized component within the broader category of packet-switching devices, the multilayer switch supports the complex requirements of today's Internet by facilitating faster and more efficient data forwarding. Its ability to handle functions across multiple OSI layers makes it a fundamental building block for robust computer networks.

## Notable For
*   Providing functionality strictly **above the data link layer**.
*   Frequently operating at the **transport layer**, a capability not found in all switching hardware.
*   Being a distinct **subclass** of the standard network switch.
*   Serving as a **component of Internet infrastructure**.

## Body
### Technical Classification
The multilayer switch is defined in knowledge bases as a specific type of computer networking device. It is formally classified as a **subclass of a network switch**. Like its parent category, it uses packet switching to forward data and serves as a main component of computer networks and Internet infrastructure.

### OSI Model Operation
The defining characteristic of a multilayer switch is its placement within the Open Systems Interconnection (OSI) model. While traditional switching is confined to the physical and data link layers, the multilayer switch is explicitly described as providing functionality **above the data link layer**.

Its operation covers the following layers:
*   **Data Link Layer:** The baseline layer for switching operations.
*   **Network Layer:** Providing capabilities typically associated with routing.
*   **Transport Layer:** Often included in its functional scope, allowing for management of end-to-end communication and data flow.

### Identifiers and Codes
The entity is tracked across various academic and knowledge management systems using specific identifiers and codes:
*   **UNSPSC:** 43222621
*   **KBpedia ID:** ContentSwitch
*   **Freebase ID:** /m/01j54j
*   **Microsoft Academic ID:** 52761205 (Note: This service has been discontinued).

## References

1. Freebase Data Dumps. 2013
2. KBpedia