Description
Overview
Flexible Bell 202 Serial Data Extensions over Packet Networks
The IP•Tube SER 202T has integrated Bell 202T modem interfaces that connect to the Bell 202T 4-Wire modem interface of Data Communication Equipment and transports their serial communication over IP Packet networks. This conversion facilitates a cost effective path for Utility and Pipeline industries to migrate their SCADA communication from end of life analog circuits to Ethernet based LAN/WAN/MAN wired and wireless networks.
Asynchronous Serial Over IP
Asynchronous characters with 5 to 8 data bits, a baud rate 1.2 kilobits, 1 or 2 stop bits, and with or without parity are efficiently encapsulated into IP packets. The latency is controlled by setting the maximum number of consecutive async characters per IP packet.
SCADA Protocol Transparency
The IP•Tube SER 202T transports asynchronous SCADA protocols transparently because of its unique TDM circuit emulation capability. RTU transmit data is encapsulated into IP packets at 64,000 samples per second and de-encapsulated at the far end at the same rate, ensuring proper RTU receive data delivery. Multiple RTUs can be IP multiplexed onto T1 circuits for routing to existing cross-connect and channel bank equipment.
IP•Tube SER 202T Standard Features
Dual LAN Interfaces
All IP•Tube SER 202T models ship with dual 10/100 BaseT Ethernet LAN ports. The dual Ethernet interfaces provide for:
- Management interface on LAN port 2 when LAN port 1 is connected to a VPN tunnel
- Protector Option for Redundant Packet Path connections with Constant or Switch Over Criteria
Assured Delivery Protocol
In order to assure high quality communications over links with intermittent or noisy performance, such as Wireless, the IP•Tube SER 202T employs Engage’s robust Assured Delivery Protocol with the following benefits:
- Packet out of sequence detection and re-sequencing
- Duplicate skipping
- Lost packet retransmissions with configured delay
IP•Tube SER 202T Optional Features
Protector Option
The protector option utilizes the second LAN interface as a redundant path for the interconnection of the IP encapsulated Bell 202T data. The extension of the Bell 202T has a fault tolerant link that is configured to always on, or with switch over criteria.
Applications
4-Wire Bell 202 Modem Over IP
Utility and Pipeline industries use 4 wire leased line communication circuits to connect remote SCADA equipment to control centers. A significant number of SCADA Remote Telemetry Units only have integrated 4 wire modem interfaces. The IP•Tube SER 202T extends the life of proven SCADA systems by converting Bell 202T 4-Wire modem interfaces to Ethernet for IP Packet network connectivity.
The IP•Tube SER 202T interfaces directly to the 4-wire analog interface of the RTU, transparently encapsulates SCADA protocols from the RTU into IP packets, and transports those packets onto the IP network. At the control center, the central site SER Bell 202T seamlessly converts the packets back into their original 202T modem data format; or directly to an RS232 DCE interface with an IP•Tube SER RS232.