Technical White Paper

Out of Band Network Management in the Central Office

Utilizing an out-of-band console server in the telco central office can help network administrators and craft personnel access serial console ports of telco control hardware in a secure and efficient manner. As the number of network elements housed in the central office continues to proliferate in number and complexity, an out-of-band management method can be a very useful tool when serial console connections are necessary.

The telco central office has the challenge of housing data network control elements as found in most corporate data centers, as well as telco specific network control hardware used specifically for carrier needs. This presents an increased number of network elements which can be controlled through serial console ports (or craft ports) and varying administrative groups who may require access to either carrier & service provider elements, data network control hardware, or both.

Serial console access and remote power control of central office IT hardware

Unique Console Ports In The Central Office

Most of the carrier and service provider hardware located in the central office are equipped with an out-of-band management port for local console connection. Historically, on-site technicians have used a local terminal or laptop and serial cable to connect to these ports using terminal emulation software. Through the out-of-band console port, telco technicians can gain root access to command and control hardware for configuration or trouble shooting.

As the central office may have several generations of carrier equipment installed, in addition to standard data center elements, many varieties of console ports are present. These console ports vary widely in terms of the physical RS-232 interface (DB-9, DB-25, RJ-45, RJ-12, RJ-11). Although the communication protocol for the console port is RS-232C, the communication parameters can vary from one network element to the other (data rate, parity, stop bits). In the telco central office, any out-of-band console server will need the basic capability of allowing independent communication parameters for each individual serial console port in the connection array.

Serial Console Servers In The Central Office

Serial console servers are a cost effective and convenient means to allow consolidation of console and craft ports for central office administrators (local or remote). A serial console server connected to every console or craft port in the central office will give administrators a powerful tool to allow quick and easy connection to these ports through a local terminal, dial-up modem, or through in-band network communications (SSH & Telnet).

A serial console server suitable for deployment in the central office should have multiple security qualities. 3rd party authentication protocols and encrypted communications (such as SSH) are necessary features of a serial console server which will be used for mission critical connection to telco control elements.

Multiple Network Administrators – One Console Server

Another trait common to the central office out-of-band management environment is the need to provide serial console access to multiple groups of administrators. A full-featured serial console server should be able to allow multiple groups to gain connection to craft ports on network elements under their specific responsibility. The need may arise for specific groups to gain access only to firewall and security elements, while other administrators may only require access to switch and router consoles.

The ability to track and log connection activity is also a tool that can be helpful when multiple administrators may use the same serial console server. A helpful feature in the serial console switch is to log user connections, record key strokes and commands, and hold this history in local non-volatile memory in addition to sending reports to SYSLOG and other data collection points.

48VDC Powered Console Server & 48VDC Power Control

If power control of network elements located in a remote central office location is required, a serial console server can be a very useful gateway to allow connection to power control tools. -48VDC power control units or ‘remote reboot units’ are increasingly popular for use with network elements that may require a cold boot or re-start after a firmware upgrade. A serial console server can be used to allow a network administrator to trouble-shoot a network element through the console port, and if necessary, connect out-of-band to the remote power control unit and initiate a complete power-cycle of the network element.

Includes Enterprise Management Software

All WTI console server and power switch products include WTI’s convenient Enterprise Management Software, which drastically simplifies the task of managing multiple console servers and power switches spread throughout your network infrastructure. The WMU Enterprise Management Software provides a centralized command interface that allows administrators to easily manage, label and control multiple WTI console servers and power switches in large network applications, reducing the time required to access console port command and power control functions on connected devices.


A serial console server unit which is central office ready should have the ability to accommodate a multitude of unique baud rates and RS-232C communication parameters since the scope of network elements found in a telco CO is so wide and varied. Serial console servers appropriate for central office deployments should also have robust security, allow for audit trail recording and SNMP control. Allowing multiple groups of administrators to access overlapping groups of network elements is also a requirement, all the while keeping local and SYSLOG reports of connections and commands for training and accountability. A comprehensive out-of-band management strategy using serial console servers in the central office is a cost effective way of ensuring network command and control availability across both in-band and out-band communications protocols.


About WTI

WTI is a California based company which designs and manufactures serial console servers and power control units. WTI has over 20 years experience in the out-of-band management market. WTI units are deployed in wide area networks in several industry sectors and serve multiple out-of-band management approaches. WTI is committed to the continual enhancement and evolution of out-of-band management tools to help the network administrator save time and increase visibility and control of the proliferating number of elements in the modern data center.