==Phrack Inc.== Volume Two, Issue 21, File 6 of 11 <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> <> <> <> Organizations Supporting The Telecommunications Network Operations <> <> <> <> NETWORK MANAGEMENT CENTER <> <> _____________________________________________________ <> <> | | <> <> | A description of the Network Management Center/NMC | <> <> | and its role in providing the best possible service | <> <> | to the customers of the telecommunications network. | <> <> |_____________________________________________________| <> <> <> <> Brought to you by <> <> Knight Lightning & Taran King <> <> <> <> August 9, 1988 <> <> <> <><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><><> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Introduction To Network Management - Southwestern Bell Telephone Company ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Modern Telecommunications Networks, relying on direct customer input and common and stored program controlled switching, are generally very reliable and have provided the means to supply low cost telecommunication service to all who desire it. Because these networks are designed on the probability that all customers do not require service simultaneously, they are engineered and equipped to provide acceptable levels of service during normal traffic load periods. When customer demands or equipment malfunctions cause a deviation from the engineered requirements or heavier than normal calling occurs, modern networks can become congested and network throughput can be affected. Network Management provides a means to improve the performance of the network during these contingencies. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Purpose And Objectives ~~~~~~~~~~~~~~~~~~~~~~ The Network Management Centers purpose is to provide the constant surveillance and control activities necessary to maintain the network at its optimum level of performance. This includes the Bell Operating Company (BOC) Intra-Lata Networks and Inter-Exchange Facilities and Circuits. NMC's objective is to meet customer and market needs and expectations, and at the same time, maximize revenues derived from the provision of network service. While the NMC cannot guarantee a certain level of service to the customer, it can ensure the most effective use of existing network capacity in all situations. This will result in: - More completed calls - Higher return on network capital investment - Better customer service - Protection of essential services such as 911, during abnormal network situations - Ensuring equal access - Assisting in national security and emergency preparedness The NMC has the capability to alter or change the switching network on a near real-time basis. This is accomplished thru Network Control Actions in the switching machines. Control messages from the NMC are acted upon by the switching machines to either expand capacity by utilizing idle equipment and trunks or to restrict the network by denying access to traffic that has a poor chance of completion, thereby freeing equipment and trunks for traffic that has a good chance of completion. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Principles And Responsibilities Of Operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In accomplishing the purpose and objective of the NMC, decision on network control actions are guided by standard principle applicable to switching technology or network architecture. All network management control actions are generally based upon at least one of the standard principles. Inhibit Switching Congestion ---------------------------- Large numbers of ineffective attempts in a switching machine due to traffic overload or equipment malfunctions can exceed the engineered capacity of the system. If not controlled, this congestion can spread to other connected switching systems. Network management controls are available that remove ineffective attempts to a congested machine, inhibiting switching congestion and preventing its spread to adjacent switching systems. Use All Available Trunks ------------------------ The switching network is sized and equipped to accommodate the average business day calling requirements. Focused overloads (storms, holidays, floods, and civil disturbances) can often result in greatly increased calling patterns for which the network is not designed. This aberration can also be caused by facility failures and switching system outages. In these cases some trunk groups are greatly overloaded while others may be virtually idle. Network management reroutes can be activated in many of these cases to use temporary idle capacity in the network, thereby completing calls that would otherwise be blocked. Keep All Trunks Filled With Messages ------------------------------------ A message is a completed call. Since the network is normally trunk limited, it is important to optimize the ratio of messages (revenue) to non-messages (non revenue producing) on any trunk group. When unusual or abnormal conditions occur in the network that cause increased short holding time calls (non-message such as busy tone, reorder tone, recorded announcement, and high-and-dry - dead air), the number of carried messages decreases because non-message traffic is occupying a larger percentage of system capacity. Network management controls are designed to reduce non-message traffic and allow more calls to complete. This results in higher customer satisfaction and increased revenue for the industry. Give Priority To Single-Link Connections ---------------------------------------- In networks designed to automatically alternate route calls, the most efficient use of available trunking occurs when traffic loads are at (or below) normal engineered values. When the engineered traffic load is exceeded, more calls alternate route and therefore are required to use more than one trunk in order to complete a call. During overload situations, the use of more than one trunk to complete a call occurs more often and the possibility of a multilink call blocking other call attempts is greatly increased. Thus, in some cases, it becomes necessary to use network management controls to limit alternate routing in order to give first routed traffic a reasonable chance to complete more calls on the network than would otherwise be completed. The responsibility of the Network Management Center is far-reaching, affecting many work groups and organizations both in Southwestern Bell Telephone Company, other telephone companies, and the customers. The NMC provides: - Real-time surveillance and control of the switching network - Identifying abnormal network situations - A centralized point for information to higher management, IC's, Independent Companies, and other BOC's. - A focal point for national security and emergency preparedness concerns - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - The System -- A Picture ~~~~~~~~~~~~~~~~~~~~~~~ The Network Management System consists of three major components: The switching network itself, the data gathering support system, and the surveillance and control system (NMC). The NMC is driven by customer actions in the switching network which are recorded and displayed via the EADAS/NM (Engineering Administration Data Acquisition System for Network Management). Network management control actions are directed from the CRT to the switching network via the same system. Diagram; Switching Data Gathering NMC Surveillance Network System and Control ____________ __________________ ______________________ / \ / \ / \ ____________ ___ _______________ | |_______________________| | | | | Access | | E | /| Display Board | | Tandem | ___ | A | / |_______________| | | | |__________| D | / | End Office |________| E | Data | A |/ | | | A |__________| S |\ | Equal | | D | Network | / | \ | Access | | A | Controls | N | \ | End Office | | S |__________| M | \ |____________| |___| | | \ __________________ | | | \ | | _|_ | | \| Cathode Ray Tube | / \ | | |__________________| \___/ |___| - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Introducing: The Southwestern Bell Telephone Company Network Management Centers ___________________ | | ___| Southwestern Bell |__________________________________________ | | Corporations | | | | | |___________________| ______|_______ ______|_______ ______|_______ | | || || | | | SW Bell || SW Bell || SW Bell | | |Mobile Systems|| Telecom || Publications | | |______________||______________||______________| __|________________ | | | Southwestern Bell | | Telephone | |___________________| | |----> Little Rock NMC Arkansas (Non EADAS/NM) (501)373-5126 |----> St. Louis NMC Missouri & Kansas (314)658-6044 |----> Oklahoma City NMC Oklahoma (405)278-5511 * |----> Dallas NMC North Texas (214)464-2164 |----> Houston NMC South Texas (713)850-5662 * * - After hours, this number goes to a beeper, at the tone, dial in your telephone number. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Summary ~~~~~~~ Network Management is the term used to describe a variety of activities associated with improving network traffic flow and customer service when abnormal conditions (unusual traffic patterns or equipment failures) may have resulted in a congested inefficient network. These activities include the application of network controls when and where necessary and planning the means by which the impact of network overloads can be minimized. Network Management is based upon the use of near real-time trunk group and switching system data and the ability to implement appropriate network controls thru the use of EADAS/NM. Network Management is concerned with completing as many calls as possible within the Intra-Lata network and providing equal treatment for the traffic flow to and from all inter-exchange carriers. "The Future Is Forever" _______________________________________________________________________________