Technical details of MSS (Mobile Switching Systems).
- Definition:
- The Mobile Switching Systems (MSS) serve as a critical component within mobile telecommunication networks.
- Their primary responsibility is to route voice and data calls between mobile devices and the Public Switched Telephone Network (PSTN).
- In essence, MSS ensures seamless communication between mobile subscribers and the rest of the network infrastructure.
- Core Functions of MSS:
- Call Routing: MSS determines how calls are directed within the network. When a mobile subscriber initiates a call, the MSS routes it to the appropriate destination (another mobile device, landline phone, or other services).
- Handover Management: During a call, if a mobile user moves from one cell to another (due to mobility or coverage reasons), the MSS manages the handover process to maintain the call continuity.
- Switching Functionalities: MSS performs essential switching tasks, including call setup, teardown, and call control.
- Network Interconnection: It facilitates connections between mobile networks and external networks (such as landlines or other mobile networks).
- Technical Aspects:
- 2G Core Network Element: MSS is primarily associated with 2G (second-generation) networks. It controls the network switching subsystem elements.
- Adaptability to GSM Networks: While originally designed for 2G, MSS can also be used in GSM networks if the manufacturer has implemented support for GSM in the MSS.
- Industry Standards and Protocols: The MSS adheres to industry open standards, including protocols like Media Gateway Control Protocol (MGCP), Megaco/H.248, Session Initiation Protocol (SIP), M2UA, and M3UA.
- Regulatory Compliance: MSS supports regulatory requirements such as E911 (emergency services), CALEA/legal intercept, wireless and local number portability, TTY/TTD (text communication for hearing-impaired users), and Number Pooling.
- Control Plane and User Plane Separation: MSS enables a split between the control plane (signaling) and the user plane (data transmission). This separation optimizes network element placement.
- MSC Server and MGW: The combination of the MSC Server (MSS) and the Media Gateway (MGW) allows cross-connection of circuit-switched calls using IP, ATM AAL2, and TDM.
- Alternate Names:
- Motorola Telephony Soft-Switch (MTS-U): Motorola terminology refers to the MSS as an MTS-U.
- Ericsson Terminology: Ericsson calls it MSC-S.
