A SAN (Storage Area Network) refers to an area of a LAN that is specifically dedicated to data storage devices, such as disk arrays, tape libraries, and file servers. A SAN is distinguished from other ways of networking storage by the low-level block storage access method used. Traffic on a SAN is very similar to those (like ATA and SCSI) used for internal disk drives. For example, a server would ask for "Block 6000 from disk drive 4". By comparison, if a file storage access method was used (like SMB or NFS), the server would request data from a particular file, and the underlying operating system would be responsible for determining which disk and block contained that data. Most SANs actually use the SCSI communications protocol to access data on the network, though they use LAN protocols at the data link and physical layer instead of SCSI.

SIP is a signaling protocol used to set up, manage, and tear down Voice-over-IP telephone calls. It is a general purpose circuit management protocol and is suitable to the setup of video conferencing, real-time document sharing, and many other IP-related types of connections. The H.323 protocol performs many of the same functions but can not be used in a general-purpose manner. H.323 predates SIP by a few years and SIP is currently the evolving to be protocol of choice for managing VoIP calls. A detailed technical discussion comparing H.323 and SIP can be referenced for more information about these two signaling methods.

A signaling protocol handles call processing functions such as dialing a number, causing a phone to ring, and indicating that a phone is busy. A signaling protocol is distinguished from the protocol that actually carries the voice data, which might be Real-Time Transport Protocol (RTP). For example, when a number is dialed at a VoIP phone, SIP would be responsible for indicating to the network that the number was dialed and initiating the call with the destination device. Once the call was initiated, RTP would carry the actual voice data. If one user hung up, SIP would indicate to the other device that the call had ended.

Prior to SIP, H.323 was the leading signaling protocol for VoIP. Whereas H.323 was defined by the International Telecommunication Union (ITU), an organization primarily focused on telephony, SIP is being defined by the Internet Engineering Task Force (IETF), the organization that defines IP protocols. As a result, SIP is more similar to common IP protocols like HTTP than it is to telephony protocols. It is human readable (data is carried as ASCII commands), very simple, and operates in a request/response model.

Although SIP is primarily used to set up voice conversations, it can be used to mediate any kind of communication session. For example, an instant messaging protocol based on SIP, called SIMPLE, has been proposed and is under development. Earthlink has created a P2P application based on SIP called SIPShare.

This global standard, defined by the International Telecommunication Union (ITU) defines the procedures and protocols by which telephones and other devices in the Public Switched Telephone Network (PSTN) interoperate in a digital environment. The standard is officially named, "Common Channel Signaling System No. 7" and is referred to typically as "SS7" and sometimes "C7". The SS7 protocols in the PSTN provide call setup, management, and teardown; wireless roaming; toll-free services, and enhanced features (call forwarding, caller-ID, 3-way calling).

Service Set Identifier. A service set is a group of devices that communicate directly to each other in a Wi-Fi 802.11 wireless network. The SSID is a text string that is the name of the group. Technically, there are two types of SSIDs. The Basic Service Set Identifier (BSSID) is the 6-byte hardware address of a wireless access point and stations within the RF signal range of that access point synchronize their activities based on information received from the access point. Multiple access points can be connected together forming an extended distribution system for communication. All of these access points are configured with an Extended Service Set Identifier (ESSID) which is what is commonly just called the "SSID". Examples of SSIDs include: "linksys", "tsunami" (the default SSID for Cisco access points), or any text string that a network administrator can think up (like "Eat A Rock" or "sales department"). The SSID shows up in the connection dialog box on a Windows-based computer.