The Lineblocs session controller is a high-performance software-based SBC that provides critical functions for communications service providers, including security and DDoS protection, network address translation, protocol interworking, and traffic management. In the graphic, two pairs of Lineblocs session controllers are deployed in a high-availability (HA) configuration, serving network-facing and subscriber-facing requirements. Deployed for network interconnection, the Lineblocs select optimal routes for voice communications traffic and assure effective interworking with outside networks. For subscriber-facing traffic management, the session controller provides packet-header manipulation and digit mapping for automatic number identification (ANI) and dialed number identification services (DNIS) manipulation.

Key functionality provided by the Lineblocs includes the following:

  • Network topology protection and asset hiding
  • Prevention of distributed denial of service (DDoS) attacks through sophisticated network security mechanisms
  • Advanced management of signaling and media throughput under all load conditions
  • Firewall and network address translation (NAT) traversal, near and far end
  • Secure Real-Time Transport Protocol (SRTP) support
  • TLS – signaling encryption
  •  Local number portability (LNP) dipping and complete control of inbound/outbound RN handling
  • Session routing based on ANI and DNIS jurisdictional control
  • Manages 90M routes in 1,000 different route tables
  • Generate call detail records (CDR) with retrieval via RADIUS, FTP, RSync, and SCP
  • Performance monitoring with metrics updated in real-time
  • Protocol interworking for SIP and H.323
  • Media transcoding, including fixed and wireless audio codecs and video codecs

The Lineblocs is the highest-performing session control platform in the market today. The software-based Lineblocs SBC runs on a compact, one-rack unit (1RU), Linux-based commercial off-the-shelf server. A single Lineblocs node scales to over 5,000 cps and 500,000 sessions. Lineblocs clusters of up to 16 nodes provide the necessary scale for any VoIP network deployment– all with greater than 99.999 percent availability. Each Lineblocs node INX can control up to 32 MST3, with each MST3 handling 14,000 G711 SRTP sessions, and 50,000 non-SRTP sessions.

The carrier-grade Lineblocs can be positioned at the core or edge of the network to manage VoIP traffic between SIP proxies, SIP UAs, H.323 gateways, IP-PBXs, and H.323 gatekeepers.

Lineblocs routing tables and LCR capabilities optimize bandwidth costs in a variety of VoIP peering applications, allowing carriers to interconnect without requiring traditional class 4 TDM switches in the call path. Replacing the relevant Class 4 functions—call routing, CDR generation, security, and network privacy—the Lineblocs also act as the “billing switch” between carriers at a fraction of the cost. VOIP providers can move the peering function off soft switches and gatekeepers to make networks more secure and reliable, and a wide range of services more profitable.

In access applications, Lineblocs VoIP session controller works in conjunction with Class 5 switches, feature servers, and gateways. The Lineblocs also enable a broad range of differentiated services while ensuring interoperability and secure firewall/NAT/call admission control. The Lineblocsi also acts as a registrar. Enforcing the borders, Lineblocs session controllers protect network topography while preventing DoS attacks to keep service provider infrastructures secure within the internal VPN. Our SBCs support SLAs and eliminate the voice-quality degradation and delays caused by multiple compression/decompressions when TDM equipment is used to switch VOIP calls between carriers. Lineblocs also interconnect to leading ENUM databases to enable providers to minimize costs by completing calls using all VoIP networks whenever possible.

Architected for profitable growth for niche applications to the world’s largest service providers, Lineblocs helps reduce not only the costs of building and managing networks but of operating services themselves. Performing multiple functions, the Lineblocs minimize the cost and complexity associated with maintaining extra gateways, soft switches, and port licenses.

Deployment Models: Lineblocs utilizes a common software code base for VoIP security, performance, and robustness whether deployed in public, private, and hybrid clouds as an appliance, software, or in the cloud. The Lineblocs virtualized session border controller can be deployed on KVM, VMware, AWS, Google, and IBM instances.