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

A) Load sharing between link 0 and link 1 under normal conditions

Link id 0, slc 0

SIU520

Link id 1, slc 1

Point Code

0x100

Link Set id 0

B) Traffic sent over link 1 under failure of link 0

SIU520

Point Code

0x100

SSP/SCP

Point Code

0x200

SSP/SCP

Point Code

0x200

Figure 3. SIU Connected to Adjacent Node with Two Links in Link Set

Failure of SS7 Links

Problem — With a single link to the adjacent signaling point, service is disrupted if the link goes down for some reason (i.e., layer 1 alarm, congestion).

Solution — Link resiliency is achieved by using multiple links between a local point code and an adjacent point code. By definition, such links are said to belong to the same link set, which can contain up to 16 links. Ideally, the links of a link set should not be carried over a unique physical medium (such as an E-1 or T-1 trunk) but, instead, should be split over independent physical trunks.

Link failure management is a standard MTP3 operation and is not an SIU520-specific feature. In other words, failure between links in a same link set will happen in a completely transparent way for the user application.

Details — In an SIU520 system configuration, two commands are used in config.txt to configure link sets and links: MTP_LINKSET and MTP_LINK. In this example, two SS7 links are defined between local point code 0x100 and adjacent point code 0x200 on time slot 16 of PCM ports 1 and 2. (Also see Figure 3.)

* MTP_LINKSET <linkset_id> <adjacent_spc> <num_links> <flags> <local_spc> <ssf> MTP_LINKSET 0 0x200 2 0x0000 0x100 0x08

*MTP_LINK <link_id> <linkset_id> <link_ref> <slc> <bpos> <blink> <bpos2> *<stream> <timeslot> <flags>

MTP_LINK 0 0 0 0 0 0 0 0 16 0x0006 MTP_LINK 1 0 1 1 0 1 0 1 16 0x0006

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Intel SIU520 SS7 manual Failure of SS7 Links, SIU Connected to Adjacent Node with Two Links in Link Set

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.