The Network Management Problems Tajudin Hassen Over

The Network Management Problems Tajudin Hassen

Over View l l l Linking together of Network Management with continuing growth in traffic types and Volumes presents main problem. The Growth adds Multiple NMS which increases operational expense Growth of associated Management overhead. Strong need to reduce the cost of ownership and improve the return on investment (ROI). Requirement of Automated flow-through actions

Requirement of Automated flowthrough actions l FCAPS areas included in the requirement l Provisioning l Detecting faults l Checking and verifying performance l Billing/accounting l Initiating repairs or network upgrades l Maintaining the network Inventory

l Contents • Bringing the Managed Data to the Code • Scalability • The Shortage of Development Skills for Creating management systems • The Shortage of Operational Skills for running Networks

Bringing the Managed Data to the Code l l l Managed objects reside on many SNMP agent hosts Copies of managed objects reside on SNMP management systems Changes in agent data may have to be regularly reconciled with the management system copy The quality of an NMS is inversely proportional to the gap between its picture of the network and the actual state of the underlying network-the smaller the gap, the better the NMS As managed NEs become more complex. An extra burden is placed on the management system.

SCALABILITY l Today’s Network is Tomorrow’s NE l Layer 2 VPN Scalability l Virtual Circuit Status Monitoring l MIB Scalability l Other Enterprise Network Scalability Issues l Large Reading Trials l Large NEs

Today’s Network is Tomorrow’s NE l. A scalability problem occurs when an increase in the number of instances of a given managed object in the network necessitates a compensating, proportional resource increase inside the management system.

Corporate Data üEnterprise Management Systems § IT Service level Management (Helpdesk solution, SLAs) § Enterprise Network, Applications and Systems management § Fault , Performance, Availability, Capacity Planning, and Bandwidth Management § Software deployment Management, inventory, metering, distribution, remote desktop control, application healing, and centralised controls e. t. c

Layer 2 VPN Scalability l. A full mesh provides the necessary connectivity for the VPN. Generally referred to as the N squre problem. l When the number of sites become very large, virtual circuits required tends to become unmanagable.

Virtual Circuit Status Monitoring l NMS l MIB attempts to read all table entries becomes very large

MIB Scalability l Network operators and their users increasingly demand l more bandwidth, l faster networks l and bigger devices.

Other Enterprise Network Scalability Issues l Scalability also affects the Enterprise l Storage solutions l Administration of firewalls l Routers, such as access control lists and static routes l Security management l Application management l Large NEs

Expensive and Scares Development Skill Sets l. A Solutions Mindset l Distributed, l Taking Creative Problem Solving Ownership l Acquiring Domain Expertise

A Solutions Mindset l Reflects the move away from the purely technological aspect of products to embrace the way enterprises and service providers look at overall solutions to business problems. l FCAPS Software layers

Distributed, Creative Problem Solving l Software l NE bugs l Performance bottlenecks l Client applications crashing intermittently l MIB table corruption l SNMP agent exception

Taking Ownership l All NMS software developers should strive to extend their portfolio of skills. l Institutional memory relates to individual developers with key knowledge of product infrastructure

Acquiring Domain Expertise l Domain expertise represents a range of detailed knowledge l Knowledge might include l Layer 2 and layer 3 traffic engineering l Layer 2 and layer 3 Qo. S l Network Management l Convergence of legacy technologies into IP l Backward and forward compatability

Linked Overviews l An ATM Linked Overview l An IP Linked Overview l Short Development Cycles l Minimizing Code Changes

Elements of NMS Development l l l l NMS Development Data Analysis Upgrade Consideration UML, Java, and Object-Oriented Development Class Design for Major NMS Features GUI Development Middleware Using CORBA-Based Products Insulating Applications from Low-Level Code

Expensive and Scarce operational Skills l The growing complexity of networks is pointing to increasingly scarce operational skills. l Multiservice Switches

MPLS: Second Chunk l l l Explicit Route Objects Resource Blocks Tunnels and LSPs In-segments and Out-segments Cross-Connects Routing Protocols Signaling Protocols Label Operations MPLS Encapsulation Qo. S and Traffic Engineering Qo. S

PROBLEMS POSED BY ENTERPRISE NETWORKING l CONNECTIVITY l LOSS OF MANAGEMENT CONTROL l ORGANIZATIONAL CHANGE REQUIREMENTS l HIDDEN COSTS OF CLIENT/SERVER COMPUTING l RELIABILITY & SECURITY *

COSTS OF CLIENT/SERVER SYSTEMS l l OPERATIONS & SUPPORT APPLICATION DEVELOPMENT HARDWARE, SOFTWARE, INSTALLATION, MAINTENANCE EDUCATION & TRAINING *

ENTERPRISE NETWORK l HARDWARE; SOFTWARE; TELECOMMUNICATIONS, DATA RESOURCES l MORE COMPUTING POWER ON THE DESKTOP l NETWORK LINKING SMALLER NETWORKS *

MPLS: Second Chunk l Explicit Route Objects l Resource Blocks l Tunnels and LSPs l In-segments and Out-segments l Cross-Connects l Routing Protocols

Explicit Route Objects l ERO is a list of layer 3 address hops inside an MPLS cloud l Describes a list of MPLS nodes through which a tunnel passes l EROs are used by signaling protocols (such as RSVP-TE) to create tunnels

Resource Blocks l Components l Maximum of resource block include reserved bandwidth l Maximum traffic burst size l Packet length

Tunnels and LSPs l MPLS-encapsulated packets enter the tunnel exhibits 3 important characters l Forwarding is based on MPLS label rather than ip header l Resource usage is fixed, based on those reserved l Path taken by the traffic is constrained by the path chosen

Cross-Connects l Point-to-Point l Point-to-multipoint l Multipoint-to-point

Routing Protocols l MPLS incorporates standard IP routing protocols such as OSPF, IS-IS and BGP 4

Router l Segments LANs into distinct networks and subnetworks; e. g. the distinct red, green and blue LANs with distinct network numbers. l Segments LANs into broadcast domains

Signaling Protocols l Signaled connections have l Resources reserved l Labels distributed l Paths selected by protocols such as RSVP_TE or LDP

Label Operations l MPLS-labeled traffic forwarded based on its encapsulation label value l Current MPLS node uses Label 2 encaps l Operations executed against labels are l Lookup l SWAP l POP l PUSH

MPLS Encapsulation l The MPLS encapsulation specifies four reserved label values 0 -IPV 4 explicit null that signals the receiving node 1 -Router alert that indicates to the receiving node 2 -IPV 6 explicit null 3 -Implicit null that signals the receiving node

Qo. S and Traffic Engineering l Providing specific chunks of bandwidth (via MPLS LSPs) to the developers. l Traffic engineering is set to become a mandatory element of converged layer 3 enterprise networks.

Qo. S l Rating traffic as being equally important l Rating VOIP traffic as being the most important l Three approaches for network services l Best effort l Fine granularity Qo. S (Int. Serv) l Coarse granularity Qo. S (Diff. Serv)

MPLS and Scalability l. A network containing possibly tens or hundreds of thousands of MPLS nodes. l It is not practical to try to read or write an object of this size using SNMP. l Tunnel-change table l Tunnel table

l Summary l Bringing managed data and code together is one of the central foundation of computing and network management l Achieving union of data and code in a scalable fashion is a problem that gets more difficult as networks grow.