Converts RS232 serial data connections into AES encrypted IP packets

Overview & Applications

The Black•Tube CEP RS232 converts RS232 serial data connections into AES encrypted IP packets, extending the serial data over very cost effective Ethernet or MPLS based LAN/WAN/MAN wired and wireless networks. Synchronous, Asynchronous, Isochronous or HDLC serial data is encrypted then encapsulated into IP packets. This facilitates the interconnection of Serial Data over IP between Serial Bulk Encryptors (KIV7/OMNI), Data Terminals, Data Acquisition Systems, WAN Routers and Bridges
and SCADA RTUs.

Layer 1 with Isochronous Support
In Layer 1 operating mode every bit is encapsulated into an IP packet. The size and frequency of the IP packets can be set with data bit rates from 75 bits to 256 kilobits per second. Isochronous serial protocols, such as Conitel, are transported synchronously to maintain message alignment. A configured number of incoming packets are buffered in order to compensate for the packet delivery jitter introduced by the network. The size of the Tube bit buffer is configurable to accommodate the peak amount of jitter.

Asynchronous Over IP
Asynchronous characters from the RS232 interface with 5 to 8 data bits, baud rates from 1.2 to 38.4 kilobits, 1 or 2 stop bits that are with or without parity are efficiently encapsulated into IP packets. The encapsulation supports block mode transfers to minimize the bandwidth required. Additionally the latency is controlled by setting the Tube Bytes per packet.

HDLC Over IP 
In Layer 2 operating mode HDLC Data frames, such as those used by Wide Area Networking protocols PPP and Frame Relay or proprietary Data Links, are transported within IP packets as HDLC over IP. The Serial to Packet conversion only occurs when HDLC frames are active.

SCADA Protocol Transparency
The Black•Tube CEP transports Bit or Byte orientated 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

Applications

Black•Tube CEP RS232 Utility Applications

NERC -CIP mandates control center redundancy. RTUs must be accessible from, and be able to connect to, multiple control centers. Black•Tube CEP continuously monitors connectivity to the active control center and automatically switches to the active backup control center (1 to 4 supported).

In order to minimize the number of analog telephone circuits required to connect Data Center Front End SCADA controllers to Substation Remote Terminal Units Multi-Drop communication protocol was implemented. The CEP Multi-Drop feature allows a single RS-232 SCADA host connection to communicate with up to 8 remote terminals over a packet based network

The Black•Tube CEP transparently supports Multi-Drop by simultaneously transmitting IP packetized Front End SCADA messages to up to eight remote Black•Tube CEPs. The Black•Tube CEP connected to the addressed RTU detects a control signal and sends the SCADA response back to the Serial interface connected to the Front End polling port.

Black•Tube CEP Management

Management Module

The Black•Tube CEP installations achieve NERC CIP compliance with a combination of internal and external functions.

Internally the Management Module software has the sophistication to implement comprehensive policies and privileges for administrator and user accounts. Administrator policy includes removal, disabling or renaming.

Interoperability with external functions such as Syslog, Network Timing Protocol, TACACS+ and Radius with its support for RSA SecureID delivers trusted compliance.