Service set identifier

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In Wi-Fi Wireless LAN computer networking, a service set identifier (SSID) is a code attached to all packets on a wireless network to identify each packet as part of that network. The code consists of a maximum of 32 alphanumeric characters. All wireless devices attempting to communicate with each other must share the same SSID. Apart from identifying each packet, SSID also serves to uniquely identify a group of wireless network devices used in a given "Service Set".

There are two major variants of the SSID.

• Ad-hoc wireless networks (IBSS) that consist of client machines without an access point use the IBSS ID (Independent Basic Service Set Identifier);
• whereas on an infrastructure network which includes an access point (BSS) or possibly an (ESS), the BSS ID or ESS ID (E for Extended) is used instead.

The naming is for convention only as the IEEE 802.11 standard dictates that an IBSS, BSS, and ESS are each defined by an SSID, otherwise known as a "Network Name". A Network Name is commonly set to the name of the network operator, such as a company name. Equipment manufacturers have liberally used all of the above SSID naming conventions to essentially describe the same thing. In some instances, the convention is wrong, as in the case of BSSID.

An extremely weak form of wireless network security is to turn off the broadcast of the SSID: to the average user there does not appear to be a network in use; it is however still readily available to crackers using the appropriate tools. This should not be the only form of defence to protect a wireless network. Other forms of encryption and authentication should also be used, WEP at the very least but preferably some form of WPA.de:Service Set Identifier es:SSID sv:SSID