Chapter 1 Data Communications and Network Management Overview

Chapter 1 Data Communications and Network Management Overview

Outline • Analogy of telephone network • Data and telecommunication network • Distributed computing environment • Internet • Protocols and standards • IT management • Network Management (NM) Model • Five Functional Areas of NM

Telephone Network • Characteristics: • Reliable - does what is expected of it • Dependable - always there when you need it • Good quality (connection) - hearing each other well • Reasons: • Good planning, design, and implementation • Good operation and management of network

Telephone Network Model

Operations Systems / NOC • Monitor telephone network parameters • S/N ratio, transmission loss, call blockage, etc. • Real-time management of network • Trunk (logical entity between switches) maintenance system measures loss and S/N. Trunks not meeting Qo. S are removed before customer notices poor quality • Traffic measurement systems measure call blockage. Additional switch planned to keep the call blockage below acceptable level • Operations systems are distributed at central offices • Network management done centrally from Network Operations Center (NOC)

Data Communication Network Message (Frame) Application Client Station Switch Server Station Switch Access Line Mobile Client Station Switch Trunk Line Switch Mobile Client Station Trunk Line Outside World Router

Internet/internet LAN WAN LAN LAN WAN : router …

Internet Configuration

Internet Topology

TCP/IP Based Networks • • TCP/IP is a suite of protocols Internet is based on TCP/IP IP is Internet protocol at the network layer level TCP is connection-oriented transport protocol and ensures end-to-end connection UDP is connectionless transport protocol and provides datagram service E-mail, WWW, FTP, Telnet: TCP/IP Network mgmt. (SNMP): UDP/IP ICMP: part of TCP/IP suite

Comparison Telephone Network TCP/IP, Internet Terminal telephone Terminal PDAs, PC, Workstations, … Application (Content) Voice Application (Content) Data: File, Message Voice, Image, Video. Bandwidth Requirement Static (64 kbps) Bandwidth Requirement Dynamic (kbps ~ Mbps) Transmission Loop: UTP Trunk: Optical Fiber Transmission Access: UTP, Coaxial Cable, … Trunk: Coaxial Cable, Optical Fiber Network Elements (NEs) CPE, Switch, Mux, Cross connect Network Elements (NEs) Hub, Switch, Bridge, Router

Comparison (cont. ) Telephone Network TCP/IP, Internet Addressing telephone number Intelligent Networks Addressing MAC, IP, Port, Domain Name, URL Network Configuration fixed, or seldom changed Network Configuration Changed frequently Growth Stable, not changed Growth grow in dog years, new applications Network Management Well planned NOCs Network Management ? Network Management Tools/Systems Less support in NEs

Protocols used in NM n SNMP(v 1, v 2, v 3) n n ICMP n n n Address Resolution Protocol/ (Reverse ARP) TCP n n Internet Control Message Protocol Ping , traceroute ARP/RARP n n Simple Network Management Protocol Socket Telnet/SSH HTTP+XML syslog

Common Network Problems • Loss of connectivity (Link, Node, Interface) • Duplicate IP address (Procedural) • Intermittent(間歇的) problems • Network configuration issues • Non-problems • Performance problems

Challenges of IT Managers • • • Reliability Non-real time problems Rapid technological advance Managing client/server environment Scalability Troubleshooting tools and systems Trouble prediction Standardization of operations - NMS helps Centralized management vs “sneaker-net”

Network Management (NM) n Definition n OAM&P of Network and Services OAM&P: Operations, Administration, Maintenance, and Provisioning) Goal n To ensure that the users of a network receive the IT services with the quality of service (Qo. S) that they expect.

Top-down View of NM functions

NM Functional Flow Chart TT Trouble Ticket NOC: Network Operation Center I&M: Installation & Maintenance

網管五大管理功能領域 n 管理功能領域 (Management Functional Areas, MFAs) n 障礙管理 (Fault Management) n 組態管理 (Configuration Management) n 安全管理 (Security Management) n 效能管理 (Performance Management) n 計量管理 (Accounting Management) ITU-T X. 700

網管五大管理功能領域 q 組態管理 (Configuration Management) q q 障礙管理 (Fault Management) q q Tells you how the network is doing. 計量管理 (Accounting Management) q q Tells you what your network is doing. 效能管理 (Performance Management) q q Tells you where everything is in the network. Tells you when your network is used. 安全管理 (Security Management) q Tells you who is using your network.

障礙管理 (Fault Management) n n n Fault Management (FM) n Detection of a problem, fault isolation and correction to normal operation. FM involves the following steps: n Discover the problem. n Isolate the problem n Fix the problem (if possible) Use of Trouble-Ticket Systems

障礙管理之功能 n n n Maintain and examine error logs Accept and act upon error detection notifications Trace and identify faults Carry out sequences of diagnostic tests Correct faults

障礙管理實例 DNS UNIX . . . User PC FDDI . . RMON Device Firewall / Router. . Internet . . UNIX Mail Server WWW Server . . . UNIX PC PC

組態管理 (Configuration Management) n Configuration Management (CM) n n The process of finding and setting up (configuring) network devices. CM identifies, exercises control over, collects data from, and provides data to networked systems.

組態管理之功能 n n n Set the parameters that control the routine operation of the networked system. Associate names with managed objects and sets of managed objects. Initialize and close down managed objects. Collect information on demand about the current condition of the networked system. Obtain announcements of significant changes in the condition of the networked system. Change the configuration of the networked system.

CM 例子: Auto Discovery

安全管理 (Security Management) n Security Management (SM) n n The process of controlling access to information on the networked system. 安全管理之功能 n n n The creation, deletion, and control of security services and mechanisms. The distribution of security-relevant information. The reporting of security-relevant events.

效能管理 (Performance Management) n Performance Management (PM) n n Measuring the performance of network hardware, software, and media. 幾個量測例子： n n Overall throughput Percentage utilization Error rate Response time

效能管理之功能 n n Gather statistical information. Maintain and examine logs of system state histories. Determine system performance under natural and artificial conditions. Alter system modes of operation for the purpose of conducting PM activities.

計量管理 (Accounting Management) n Accounting Management (AM) n n Tracking each individual and group user's utilization of network resources to better ensure that users have sufficient resources. AM enables charges to be established for the use of network resources, and the costs to be identified for the use of those network resources.

計量管理之功能 n n n Inform users of costs incurred or resources consumed. Enable accounting limits to be set and tariff schedules to be associated with the use of resources. Enable costs to be combined where multiple resources are invoked to achieve a given communication objective.

Interoperability (cont. ) Services & Protocols

Network Management Model Management Station MA Management Operation Response Event Manager Network Element MO Agent Communication Protocols Network Legend： MA: Manager Applications MO: Managed Objects R: Real Resource R

網路管理構成元素 n n 管理者 (Manager) 代理者 (Agent) 網路管理通信協定 (Network Management Protocol) 網路管理資訊 (Network Management Information)

Source: IEEE Communications Magazine • May 1993

Status and Future Trends • Status: • SNMP management • Limited CMIP management • Operations systems • Polled systems • Future trends: • Object-oriented approach • Service and policy management • Business management • Web-based management

管理金字塔 (Management Pyramid) Business Management Service Management Network Management Element Management Network Elements

Functional Areas Network Types Configuration Stages Performance IN VPN Accounting Corporate Network Change Fault WAN Operation MAN Accounting LAN Installation Planning 管理範圍 ? Network Management System Management Applications Management Service Management Eneterprise Management Disciplines Data Voice Video Multimedia Information Types

網路管理基本方式 network NM PC UNIX . . . 網管系統 FDDI . . RMON Device Polling Firewall / Router. . Internet Notification . . UNIX PC PC