Building Fault-tolerant SS7 Systems Using the Intel® NetStructure™ SIU520 SS7 Signaling Gateway Application Note

A) Normal routing case

Single Point Code

Inter-SIU

Link Set

SIUA

Link Set id 0

SIUB

F-LinksSSP/SCP

Link Set id 1

B) Routing under network link failure

Inter-SIU

Link Set

Link Set id 0

Single Point Code

SIUA

SSP/SCP

SIUB

Link Set id 1

Figure 6. Transmit Routing to a Single Destination

partner SIU across the inter-SIU link set and sent out to the adjacent signaling point by the partner unit. The inter- SIU link set also provides the capability of message retrieval and retransmission when a changeover operation occurs between the two units.

For circuit-switched applications, the circuit groups are configured on both units, letting the application select which SIU controls each group. In normal operation, the control of circuit groups is distributed between both the SIUA and SIUB. In the event of failure of a unit

(or for maintenance), the application can move control of each circuit group from one SIU to the other.

For transaction-based applications, the transactions are shared equally between the two units.

Routing Architectures of a Dual-resilient SIU System

The routing options (i.e., straight connection to the DPC vs. indirect connection via a pair of STPs) described in this section will vary based on the actual network architec- ture that is being supported for a particular application.

Connection to a Single Adjacent Signaling Point

Figure 6 shows two possible routing alternatives for SIUA routing to an adjacent SSP or SCP. Messages issued

from SIUA are sent to the destination SSP or SCP using local SS7 links if available. If these fail, transmit messages are relayed through SIUB over the inter-SIU links. In this case, the DPC is also the adjacent signaling point. Although Figure 6 shows an SIU pair connected to a sin- gle adjacent signaling point, the pair may be connected to multiple destinations.

The number of links allocated in the inter-SIU link set has to be carefully calculated. Since these links will be used for outgoing traffic only, they can be used at a higher capacity than network-facing links. Moreover, since only half of the traffic can potentially be routed through that link set, a common rule is to allocate a fourth of the total number of network-facing links in the inter-SIU link set. In a fully populated pair of SIU520 (12 links per unit; 24 links total), 16 links will be typically allocated in the network- facing link set and four links will be allocated in the inter- SIU link set.

Routes to destinations are configured such that there is a primary link set (the link set from the SIU to the DPC) and a secondary link set (the inter-SIU link set) which is used only when the primary link set has failed.

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Intel SIU520 SS7 Routing Architectures of a Dual-resilient SIU System, Connection to a Single Adjacent Signaling Point

SIU520 SS7 specifications

The Intel SIU520 SS7 is a significant advancement in the realm of telecommunications, specifically designed for seamless signaling in a wide array of telecommunication infrastructures. As a part of Intel's pioneering suite of products, the SIU520 plays a critical role in managing signaling for telephony systems that require efficient handling of SS7 protocols.

One of the main features of the SIU520 is its support for the SS7 signaling protocol, which is pivotal for the establishment and management of telephone calls over traditional circuit-switched networks. With its robust design, the SIU520 ensures reliability in signaling, contributing to the reduction of call set-up times and the minimization of errors, thus enhancing the overall quality of communication services.

The SIU520 incorporates advanced technologies such as high-speed data processing capabilities, allowing it to handle multiple signaling messages concurrently. This is particularly important in environments with high call volumes, where efficient processing can significantly affect the performance of telecommunication services. Furthermore, the architecture of the SIU520 is designed for scalability, enabling easy integration into existing infrastructures while accommodating future expansions as demand increases.

Another characteristic that sets the SIU520 apart is its support for various signaling types beyond standard SS7, including ISDN and SIP. This makes it a versatile tool for service providers aiming to offer diverse services, such as voice, video, and data communications. The SIU520 is also designed with a focus on interoperability, which ensures that it can effectively communicate with equipment from different manufacturers, thus providing flexibility in deployment.

In terms of security features, the SIU520 is architected to withstand common threats in the communication landscape. It employs encryption and authentication protocols to safeguard signaling traffic, ensuring that sensitive information remains protected during transmission.

In summary, the Intel SIU520 SS7 represents a robust and flexible signaling solution crucial for modern telecommunications. With its support for multiple protocols, high processing speeds, scalability, and secure communication capabilities, it stands as a testament to Intel's commitment to advancing telecommunication technologies and enhancing the efficiency and reliability of communication networks worldwide.