Architecture

Our Communications Network

Our advantage over competitors stems from our company focus on providing the very best quality service that can be depended on by our clients. To ensure service reliability, we use a large number of highly reliable SMSC platforms from established and reputable mobile operators and other SMS gateway in addition to our very own SS7 SMSCs. This delivery network is constantly monitored and dynamic routing changes made to mitigate delivery issues.

Our SMSCs compliment connections with established mobile operators and provide exciting service opportunities for HSL and their clients. As with all core messaging software systems operated by HSL, the SMSCs are the result of internal development by HSL’s software engineering team. The currently deployed SMSCs located on HSL’s SS7 network are connected to mobile networks in the UK and other networks worldwide via the global SS7 network.

Our SMSCs contain integrated HLR (Home Location Register) and MSC (Mobile Switching Centre) capability and have a high degree of functionality for inbound and outbound (MO/MT) SMS. SMSC platforms communicate directly with the SS7 network to provide low latency, highly reliable channels for SMS delivery.

Other key elements of our infrastructure include our own SS7 STPs (Signalling Transfer Points), multiple data centre sites (four of which are located in the UK) and high availability links between sites, SMSCs and mobile networks. This infrastructure provides clients with a wide coverage of over 800 mobile networks worldwide.

Data Centres

Our services are provided using our own server infrastructure and cloud-based servers located at separate and independent geographical sites located across Europe. At least two of these points of presence allow clients to access our network. The infrastructure is designed to ensure service availability is not affected if there is a failure at a site.

Within each site we have redundancy to ensure that the failure of equipment comprising our service does not cause an impact to service.  We strongly believe in clusters of servers, active-standby pairs and load balancers!

Our philosophy when deploying services and the infrastructure is that the service should always be available, should work reliably and should not require human intervention to restore service in the event of a failure.  We fully accept that failures will occur but we don’t accept that you should wait on our engineers in order to restore service.

Service is highly available and is consistently reliable so that customers can depend on our services in small and great tasks. 

What you have to do

If you’re using a session based API and you lose your connection to the service then simply attempt an immediate reconnect to the service and all should continue fine. When using the SMPP API it’s possible for you to maintain the same session to our systems without interruption for weeks or months on end.

When using the SMTP APIs your email server will (and must) use MX records to determine which of our email servers to send your messages. The use of MX records allows you to automatically work around the unavailability of an individual email server or site without intervention by you or special handling by your application.