CIS 551 / TCOM 401 Computer and Network Security
|
|
|
- Eileen Cain
- 5 years ago
- Views:
Transcription
1 CIS 551 / TCOM 401 Computer and Network Security Spring 2008 Lecture 12 2/28/08 CIS/TCOM 551 1
2 Announcements Reminder: Project 2 is due Friday, March 7th at 11:59 pm 2/28/08 CIS/TCOM 551 2
3 Internet Protocol Interoperability FTP HTTP NV TFTP TCP Overlays (running at hosts) UDP IP Virtual Network Infrastructure (runs globally) Networks (run locally) Ethernet ATM FDDI 2/28/08 CIS/TCOM 551 3
4 Internetworks Router (Gateway) 2/28/08 CIS/TCOM 551 4
5 Internetworks H1 H2 H3 Ethernet Ethernet H7 R3 H8 R1 H4 Point-to-Point Link (e.g., ISDN) FDDI Token Ring R2 H5 H6 2/28/08 CIS/TCOM 551 5
6 IP Encapsulation H1 TCP R1 R2 R3 H8 TCP IP IP IP IP IP ETH ETH FDDI FDDI PPP PPP ETH ETH Example of protocol layers used to transmit from H1 to H8 in network shown on previous slide. 2/28/08 CIS/TCOM 551 6
7 IP Service Model Choose minimal service model All nets can implement Tin cans and a string extremum Features: Best-effort datagram delivery Reliability, etc. as overlays (as in TCP/IP) Packet format standardized 2/28/08 CIS/TCOM 551 7
8 IPv4 Packet Format Version Hlen TOS Length Ident Flags Offset TTL Protocol Checksum SourceAddr DestinationAddr Options (variable length) Pad DATA 2/28/08 CIS/TCOM 551 8
9 Fields of IPv4 Header Version Version of IP, example header is IPv4 First field so easy to implement case statement Hlen Header length, in 32-bit words TOS Type of Service (rarely used) Priorities, delay, throughput, reliability Length Length of datagram, in bytes 16 bits, hence max. of 65,536 bytes Fields for fragmentation and reassembly Identifier Flags Offset 2/28/08 CIS/TCOM 551 9
10 Header fields, continued TTL Time to live (in reality, hop count) 64 is the current default (128 also used) Protocol e.g., TCP (6), UDP(17), etc. Checksum Checksum of header (not CRC) If header fails checksum, discard the whole packet SourceAddr, DestinationAddr 32 bit IP addresses - global, IP-defined Options length can be computed using Hlen 2/28/08 CIS/TCOM
11 IP Datagram Delivery Every IP packet (datagram) contains the destination IP address The network part of the address uniquely identifies a single network that is part of the larger Internet. All hosts and routers that share the same network part of their address are connected to the same physical network. Routers can exchange packets on any network they re attached to. 2/28/08 CIS/TCOM
12 IP addresses Hierarchical, not flat as in Ethernet Network Host A Network Host B Network Host C Written as four decimal numbers separated by dots: /28/08 CIS/TCOM
13 Network Classes Class # of nets # of hosts per net A 126 ~16 million B C ~2 million 254 2/28/08 CIS/TCOM
14 IP Forwarding algorithm If (Network # dest == Network # interface) then deliver to destination over interface else if (Network # dest in forwarding table) deliver packet to NextHop router else deliver packet to default router Forwarding tables Contain (Network #, NextHop) pairs Additional information Built by routing protocol that learns the network topology, adapts to changes 2/28/08 CIS/TCOM
15 Subnetting Problem: IP addressing scheme leads to fragmentation A class B network with only 300 machines on it wastes > 65,000 addresses Need a way to divide up a single network address space into multiple smaller subnetworks. Idea: One IP network number allocated to several physical networks. The multiple physical networks are called subnets Should be close together (why?) Useful when a large company (or university!) has many physical networks. 2/28/08 CIS/TCOM
16 Subnet Numbers Solution: Subnetting All nodes are configured with subnet mask Allows definition of a subnet number All hosts on a physical subnetwork share the same subnet number Subnet Mask ( ) Subnetted Address: Network number Subnet ID Host ID 2/28/08 CIS/TCOM
17 Example of Subnetting Subnet mask: Subnet #: H R R1 Subnet mask: Subnet #: H H Subnet mask: Subnet #: /28/08 CIS/TCOM
18 Subnets, continued Mask is bitwise-anded with address This is done at routers Router tables in this model: <Subnet #, Subnet Mask, NextHop> Subnetting allows a set of physical networks to look like a single logical network from elsewhere 2/28/08 CIS/TCOM
19 Forwarding Algorithm D = destination IP address for each forwarding table entry (SubnetNumber, SubnetMask, NextHop) D1 = SubnetMask & D if D1 = SubnetNumber if NextHop is an interface deliver datagram directly to destination else deliver datagram to NextHop (router) Deliver datagram to default router (if above fails) 2/28/08 CIS/TCOM
20 ARP - Address Resolution Protocol Problem: Need mapping between IP and link layer addresses. Solution: ARP Every host maintains IP Link layer mapping table (cache) Timeout associated with cached info (15 min.) Sender Broadcasts Who is IP addr X? Broadcast message includes sender s IP & Link Layer address Receivers Any host with sender in cache refreshes time-out Host with IP address X replies IP X is Link Layer Y Target host adds sender (if not already in cache) 2/28/08 CIS/TCOM
21 ICMP: Internet Control Message Protocol Collection of error & control messages Sent back to the source when Router or Host cannot process packet correctly Error Examples: Destination host unreachable Reassembly process failed TTL reached 0 IP Header Checksum failed Control Example: Redirect tells source about a better route 2/28/08 CIS/TCOM
22 Domain Name System System for mapping mnemonic names for computers into IP addresses. zeta.cis.upenn.edu Domain Hierarchy Name Servers 13 Root servers map top-level domains such as ".com" or ".net" (Why 13? Early UDP protocol supported only 512 bytes ) Name Resolution Protocol for looking up hierarchical domain names to determine the IP address Protocol runs on UDP port 53 2/28/08 CIS/TCOM
23 Domain Name Hierarchy edu com gov mil org net cornell upenn cisco yahoo nasa nsf arpa navy cis seas wharton 2/28/08 CIS/TCOM
24 Hierarchy of Name Servers Root Name Server Cornell Name Server Upenn Name Server CIS Name Server SEAS Name Server Wharton Name Server 2/28/08 CIS/TCOM
25 Records on Name Servers < Name, Type, Class, TTL, RDLength, RDATA > Name of the node Types: A Host to address mappings NS Name server address mappings CNAME Aliases MX Mail exchange server mappings others Class IN for IP addresses 2/28/08 CIS/TCOM
26 Name resolution client Local Name server Root Name server edu Name server upenn Name server /28/08 CIS/TCOM
27 DNS Vulnerabilities See "Corrupted DNS Resolution Paths: The rise of a malicious resolution authority" by Dagon et al. Rogue DNS Servers Compromised DNS servers that answer incorrectly DNS Cache Poisoning Request: subdomain.example.com IN A Reply: Answer: (no response) Authority section: example.com IN ns.wikipedia.org. Additional section: ns.wikipedia.org IN A w.x.y.z 2/28/08 CIS/TCOM
28 Reflected denial of service ICMP message with an "echo request" is called 'ping' Broadcast a ping request For sender s address put target s address All hosts reply to ping, flooding the target with responses Hard to trace Hard to prevent Turn off ping? (Makes legitimate use impossible) Limit with network configuration by restricting scope of broadcast messages Sometimes called a "smurf attack" 2/28/08 CIS/TCOM
29 (Distributed) Denial of Service Coordinate multiple subverted machines to attack Flood a server with bogus requests TCP SYN packet flood > 600,000 packets per second Detection & Assessment? 12,800 attacks at 5000 hosts! (in 3 week period during 2001) IP Spoofing (forged source IP address) Feb : 6 of 13 root servers suffered DDoS attack Oct : 9 of 13 root servers were swampted Prompted changes in the architecture Prevention? Filtering? Decentralized file storage? 2/28/08 CIS/TCOM
CIS 551 / TCOM 401 Computer and Network Security. Spring 2006 Lecture 16
CIS 551 / TCOM 401 Computer and Network Security Spring 2006 Lecture 16 Announcements Midterm II March 21st (One week from today) In class Same format as last time Will cover all material since Midterm
Computer and Network Security
CIS 551 / TCOM 401 Computer and Network Security Spring 2009 Lecture 7 Announcements First project: Due: TOMORROW at 11:59 p.m. http://www.cis.upenn.edu/~cis551/project1.html Plan for Today: Networks:
CIS 551 / TCOM 401 Computer and Network Security. Spring 2007 Lecture 8
CIS 551 / TCOM 401 Computer and Network Security Spring 2007 Lecture 8 Announcements Reminder: Project 1 is due on tonight by midnight. Midterm 1 will be held next Thursday, Feb. 8th. Example midterms
Lecture 8. Basic Internetworking (IP) Outline. Basic Internetworking (IP) Basic Internetworking (IP) Service Model
Lecture 8 Basic Internetworking (IP) Reminder: Homework 3, Programming Project 2 due on Tuesday. An example internet is shown at right. Routers or gateways are used to connect different physical networks.
Lecture 8. Reminder: Homework 3, Programming Project 2 due on Thursday. Questions? Tuesday, September 20 CS 475 Networks - Lecture 8 1
Lecture 8 Reminder: Homework 3, Programming Project 2 due on Thursday. Questions? Tuesday, September 20 CS 475 Networks - Lecture 8 1 Outline Chapter 3 - Internetworking 3.1 Switching and Bridging 3.2
CS475 Networks Lecture 8 Chapter 3 Internetworking. Ethernet or Wi-Fi).
Assignments Reading for Lecture 9: Section 3.3 3.2 Basic Internetworking (IP) Bridges and LAN switches from last section have limited ability CS475 Networks Lecture 8 Chapter 3 Internetworking is a logical
Internet Protocol. Outline Introduction to Internet Protocol Header and address formats ICMP Tools CS 640 1
Internet Protocol Outline Introduction to Internet Protocol Header and address formats ICMP Tools CS 640 1 Internet Protocol Runs on all hosts in the Internet and enables packets to be routed between systems
IP - The Internet Protocol. Based on the slides of Dr. Jorg Liebeherr, University of Virginia
IP - The Internet Protocol Based on the slides of Dr. Jorg Liebeherr, University of Virginia Orientation IP (Internet Protocol) is a Network Layer Protocol. IP: The waist of the hourglass IP is the waist
Recap. Recap. Internetworking. First mile problem. Internet. End Users. Last mile problem. Direct link networks Packet switching.
Recap First mile problem Internet www.yahoo.com Comcast Sprint End Users SBC UUNET www.cnn.com Last mile problem Recap Direct link networks Packet switching Internetworking 1 IP Internet Concatenation
Internetworking Part 2
CMPE 344 Computer Networks Spring 2012 Internetworking Part 2 Reading: Peterson and Davie, 3.2, 4.1 19/04/2012 1 Aim and Problems Aim: Build networks connecting millions of users around the globe spanning
The Internet. Overview. Network building blocks
The Internet Lecture 24 Based in part on material from Computer Networks: A Systems Approach by Larry Peterson & Bruce Davie CS 638 Web Programming Overview Network building blocks Nodes: PC, special-purpose
The Internet Protocol (IP)
The Internet Protocol (IP) The Blood of the Internet (C) Herbert Haas 2005/03/11 "Information Superhighway is really an acronym for 'Interactive Network For Organizing, Retrieving, Manipulating, Accessing
McGraw-Hill The McGraw-Hill Companies, Inc., 2000
!! McGraw-Hill The McGraw-Hill Companies, Inc., 2000 "#$% & '$# )1 ) ) )6 ) )* )- ). )0 )1! )11 )1 )1 )16 )1 3'' 4", ( ( $ ( $ $$+, $$, /+ & 23,4 )/+ &4 $ 53" Network Layer Position of network layer Figure
Computer and Network Security
CIS 551 / TCOM 401 Computer and Network Security Spring 2009 Lecture 8 Announcements Plan for Today: Networks: TCP Firewalls Midterm 1: One week from Today! 2/17/2009 In class, short answer, multiple choice,
OSI Network Layer. Network Fundamentals Chapter 5. Version Cisco Systems, Inc. All rights reserved. Cisco Public 1
OSI Network Layer Network Fundamentals Chapter 5 Version 4.0 1 Objectives Identify the role of the Network Layer, as it describes communication from one end device to another end device. Examine the most
CSE/EE 461 The Network Layer. Application Presentation Session Transport Network Data Link Physical
CSE/EE 461 The Network Layer Application Presentation Session Transport Network Data Link Physical This Lecture Focus: What to do when one wire isn t big enough? Point to point link Broadcast link (Ethernet
Outline. Routing. Introduction to Wide Area Routing. Classification of Routing Algorithms. Introduction. Broadcasting and Multicasting
Outline Routing Fundamentals of Computer Networks Guevara Noubir Introduction Broadcasting and Multicasting Shortest Path Unicast Routing Link Weights and Stability F2003, CSG150 Fundamentals of Computer
Internetworking Part 2
CMPE 344 Computer Networks Spring 2012 Internetworking Part 2 Reading: Peterson and Davie, 3.2, 4.1 16/08/2018 1 Aim and Problems Aim: Build networks connecting millions of users around the globe spanning
Interconnecting Networks with TCP/IP
Chapter 8 Interconnecting s with TCP/IP 1999, Cisco Systems, Inc. 8-1 Introduction to TCP/IP Internet TCP/IP Early protocol suite Universal 1999, Cisco Systems, Inc. www.cisco.com ICND 8-2 TCP/IP Protocol
ECE 4450:427/527 - Computer Networks Spring 2017
ECE 4450:427/527 - Computer Networks Spring 2017 Dr. Nghi Tran Department of Electrical & Computer Engineering Lecture 6.2: IP Dr. Nghi Tran (ECE-University of Akron) ECE 4450:427/527 Computer Networks
IP Protocols. ALTTC/Oct
IP Protocols Internet or IP technology over the years has emerged as the most prominent data communication technology. TCP/IP protocol has become de-facto data comm standard throughout the world. It can
Vorlesung Kommunikationsnetze
Picture 15 13 Vorlesung Kommunikationsnetze Prof. Dr. H. P. Großmann mit B. Wiegel sowie A. Schmeiser und M. Rabel Sommersemester 2009 Institut für Organisation und Management von Informationssystemen
Interconnecting Networks with TCP/IP. 2000, Cisco Systems, Inc. 8-1
Interconnecting Networks with TCP/IP 2000, Cisco Systems, Inc. 8-1 Objectives Upon completion of this chapter you will be able to perform the following tasks: Identify the IP protocol stack, its protocol
TSIN02 - Internetworking
Lecture 2: Internet Protocol Literature: Forouzan: ch (4-6), 7-9 and ch 31 2004 Image Coding Group, Linköpings Universitet Lecture 2: IP Goals: Understand the benefits Understand the architecture IPv4
CS 457 Networking and the Internet. Problems. Mechanisms 9/21/16. Fall 2016 Indrajit Ray
CS 457 Networking and the Internet Fall 2016 Indrajit Ray Problems Earlier we saw how to connect one node to another, or to an existing network. How do we build networks of global scale? How do we interconnect
ARP, IP. Chong-Kwon Kim. Each station (or network interface) should be uniquely identified Use 6 byte long address
ARP, IP Chong-Kwon Kim Routing Within a LAN MAC Address Each station (or network interface) should be uniquely identified Use 6 byte long address Broadcast & Filter Broadcast medium Signals are transmitted
Lecture 17 Overview. Last Lecture. Wide Area Networking (2) This Lecture. Internet Protocol (1) Source: chapters 2.2, 2.3,18.4, 19.1, 9.
Lecture 17 Overview Last Lecture Wide Area Networking (2) This Lecture Internet Protocol (1) Source: chapters 2.2, 2.3,18.4, 19.1, 9.2 Next Lecture Internet Protocol (2) Source: chapters 19.1, 19.2, 22,1
Configuring IP Services
This module describes how to configure optional IP services. For a complete description of the IP services commands in this chapter, refer to the Cisco IOS IP Application Services Command Reference. To
Layer 4: UDP, TCP, and others. based on Chapter 9 of CompTIA Network+ Exam Guide, 4th ed., Mike Meyers
Layer 4: UDP, TCP, and others based on Chapter 9 of CompTIA Network+ Exam Guide, 4th ed., Mike Meyers Concepts application set transport set High-level, "Application Set" protocols deal only with how handled
ECE4110 Internetwork Programming. Introduction and Overview
ECE4110 Internetwork Programming Introduction and Overview 1 EXAMPLE GENERAL NETWORK ALGORITHM Listen to wire Are signals detected Detect a preamble Yes Read Destination Address No data carrying or noise?
DDoS Testing with XM-2G. Step by Step Guide
DDoS Testing with XM-G Step by Step Guide DDoS DEFINED Distributed Denial of Service (DDoS) Multiple compromised systems usually infected with a Trojan are used to target a single system causing a Denial
Introduction to Internetworking
Introduction to Internetworking Introductory terms Communications Network Facility that provides data transfer services An internet Collection of communications networks interconnected by bridges and/or
Network Layer/IP Protocols
Network Layer/IP Protocols 1 Outline IP Datagram (IPv4) NAT Connection less and connection oriented service 2 IPv4 packet header 3 IPv4 Datagram Header Format version of the IP protocol (4 BIts) IP header
CHAPTER-2 IP CONCEPTS
CHAPTER-2 IP CONCEPTS Page: 1 IP Concepts IP is a very important protocol in modern internetworking; you can't really comprehend modern networking without a good understanding of IP. Unfortunately, IP
Agenda L2 versus L3 Switching IP Protocol, IP Addressing IP Forwarding ARP and ICMP IP Routing First Hop Redundancy
Primer IP Technology L2 Ethernet Switching versus L3 routing IP Protocol, IP Addressing, IP Forwarding ARP and ICMP IP Routing, OSPF Basics First Hop Redundancy (HSRP) Agenda L2 versus L3 Switching IP
Chapter 3 Internetworking
Chapter 3 Internetworking Basic Internetworking (IP) (cont d) Datagram forwarding in IP Every datagram contains the IP address of the destination host If directly connected to destination network, then
Introduction to Internetworking
Introduction to Internetworking Stefano Vissicchio UCL Computer Science COMP0023 Internetworking Goal: Connect many networks together into one Internet. Any computer can send to any other computer on any
Internet Layers. Physical Layer. Application. Application. Transport. Transport. Network. Network. Network. Network. Link. Link. Link.
Internet Layers Application Application Transport Transport Network Network Network Network Link Link Link Link Ethernet Fiber Optics Physical Layer Wi-Fi ARP requests and responses IP: 192.168.1.1 MAC:
Introduction to routing in the Internet
Introduction to routing in the Internet Internet architecture IPv4, ICMP, ARP Addressing, routing principles (Chapters 2 3 in Huitema) Internet-1 Internet Architecture Principles End-to-end principle by
EC441 Fall 2018 Introduction to Computer Networking Chapter4: Network Layer Data Plane
EC441 Fall 2018 Introduction to Computer Networking Chapter4: Network Layer Data Plane This presentation is adapted from slides produced by Jim Kurose and Keith Ross for their book, Computer Networking:
TCP /IP Fundamentals Mr. Cantu
TCP /IP Fundamentals Mr. Cantu OSI Model and TCP/IP Model Comparison TCP / IP Protocols (Application Layer) The TCP/IP subprotocols listed in this layer are services that support a number of network functions:
TCP/IP THE TCP/IP ARCHITECTURE
TCP/IP-1 The Internet Protocol (IP) enables communications across a vast and heterogeneous collection of networks that are based on different technologies. Any host computer that is connected to the Internet
Applied Networks & Security
Applied Networks & Security TCP/IP Networks with Critical Analysis http://condor.depaul.edu/~jkristof/it263/ John Kristoff jtk@depaul.edu IT 263 Spring 2006/2007 John Kristoff - DePaul University 1 Critical
The Internetworking Problem. Internetworking. A Translation-based Solution
Cloud Cloud Cloud 1 The Internetworking Problem Internetworking Two nodes communicating across a network of networks How to transport packets through this heterogeneous mass? A B The Internetworking Problem
CS 356: Computer Network Architectures. Lecture 10: IP Fragmentation, ARP, and ICMP. Xiaowei Yang
CS 356: Computer Network Architectures Lecture 10: IP Fragmentation, ARP, and ICMP Xiaowei Yang xwy@cs.duke.edu Overview Homework 2-dimension parity IP fragmentation ARP ICMP Fragmentation and Reassembly
CompSci 356: Computer Network Architectures. Lecture 8: Spanning Tree Algorithm and Basic Internetworking Ch & 3.2. Xiaowei Yang
CompSci 356: Computer Network Architectures Lecture 8: Spanning Tree Algorithm and Basic Internetworking Ch 3.1.5 & 3.2 Xiaowei Yang xwy@cs.duke.edu Review Past lectures Single link networks Point-to-point,
CS 348 Computer Networks. IP and Routing. Indian Institute of Technology, Bombay
Computer Networks IP and Routing Network Interconnections Data Link Layer Delivery of frames on the same LAN Extend reach using switches/bridges and hubs Limitations Solution? Cannot address heterogeniety
CPSC 826 Internetworking. The Network Layer: Routing & Addressing Outline. The Network Layer
1 CPSC 826 Intering The Network Layer: Routing & Addressing Outline The Network Layer Michele Weigle Department of Computer Science Clemson University mweigle@cs.clemson.edu November 10, 2004 Network layer
Networking Basics. EC512 Spring /15/2015 EC512 - Prof. Thomas Skinner 1
Networking Basics EC512 Spring 2015 2/15/2015 EC512 - Prof. Thomas Skinner 1 Protocols Protocols are required in order to allow information to be extracted from the stream of bits flowing from one point
The Internet Protocol. IP Addresses Address Resolution Protocol: IP datagram format and forwarding: IP fragmentation and reassembly
The Internet Protocol IP Addresses Address Resolution Protocol: IP datagram format and forwarding: IP fragmentation and reassembly IP Addresses IP Addresses are 32 bit. Written in dotted decimal format:
CS 457 Lecture 11 More IP Networking. Fall 2011
CS 457 Lecture 11 More IP Networking Fall 2011 IP datagram format IP protocol version number header length (bytes) type of data max number remaining hops (decremented at each router) upper layer protocol
ET4254 Communications and Networking 1
Topic 9 Internet Protocols Aims:- basic protocol functions internetworking principles connectionless internetworking IP IPv6 IPSec 1 Protocol Functions have a small set of functions that form basis of
CSCI-1680 Network Layer: IP & Forwarding Rodrigo Fonseca
CSCI-1680 Network Layer: IP & Forwarding Rodrigo Fonseca Based partly on lecture notes by David Mazières, Phil Levis, John Janno< Administrivia IP out today. Your job: Find partners and tell us Implement
Introduction to routing in the Internet
Introduction to routing in the Internet Internet architecture IPv4, ICMP, ARP Addressing, routing principles (Chapters 2 3 in Huitema) Internet-1 Internet Architecture Principles End-to-end principle by
Guide to Networking Essentials, 6 th Edition. Chapter 5: Network Protocols
Guide to Networking Essentials, 6 th Edition Chapter 5: Network Protocols Objectives Describe the purpose of a network protocol, the layers in the TCP/IP architecture, and the protocols in each TCP/IP
Internet Protocol (IP)
CPSC 360 - Network Programming Internet Protocol (IP) Michele Weigle Department of Computer Science Clemson University mweigle@cs.clemson.edu March 14, 2005 http://www.cs.clemson.edu/~mweigle/courses/cpsc360
ICS 351: Networking Protocols
ICS 351: Networking Protocols IP packet forwarding application layer: DNS, HTTP transport layer: TCP and UDP network layer: IP, ICMP, ARP data-link layer: Ethernet, WiFi 1 Networking concepts each protocol
RMIT University. Data Communication and Net-Centric Computing COSC 1111/2061. Lecture 2. Internetworking IPv4, IPv6
RMIT University Data Communication and Net-Centric Computing COSC 1111/2061 Internetworking IPv4, IPv6 Technology Slide 1 Lecture Overview During this lecture, we will understand The principles of Internetworking
Network Layer: Control/data plane, addressing, routers
Network Layer: Control/data plane, addressing, routers CS 352, Lecture 10 http://www.cs.rutgers.edu/~sn624/352-s19 Srinivas Narayana (heavily adapted from slides by Prof. Badri Nath and the textbook authors)
Internet. Organization Addresses TCP/IP Protocol stack Forwarding. 1. Use of a globally unique address space based on Internet Addresses
Internet Organization Addresses TCP/IP Protocol stack Forwarding Jörg Liebeherr, 1998-2003 1 What defines the Internet? 1. Use of a globally unique address space based on Internet Addresses 2. Support
ECE 158A: Lecture 7. Fall 2015
ECE 158A: Lecture 7 Fall 2015 Outline We have discussed IP shortest path routing Now we have a closer look at the IP addressing mechanism We are still at the networking layer, we will examine: IP Headers
ICS 451: Today's plan
ICS 451: Today's plan ICMP ping traceroute ARP DHCP summary of IP processing ICMP Internet Control Message Protocol, 2 functions: error reporting (never sent in response to ICMP error packets) network
ECPE / COMP 177 Fall Some slides from Kurose and Ross, Computer Networking, 5 th Edition
ECPE / COMP 177 Fall 2012 Some slides from Kurose and Ross, Computer Networking, 5 th Edition Application Layer Transport Layer Network Layer Link Layer Physical Layer 2 Application Layer HTTP DNS IMAP
Data Communication Prof. A. Pal Department of Computer Science & Engineering Indian Institute of Technology, Kharagpur Lecture 34 TCP/ IP I
Data Communication Prof. A. Pal Department of Computer Science & Engineering Indian Institute of Technology, Kharagpur Lecture 34 TCP/ IP I Hello and welcome to today s lecture on TCP/IP. (Refer Slide
Inter-networking. Problem. 3&4-Internetworking.key - September 20, LAN s are great but. We want to connect them together. ...
1 Inter-networking COS 460 & 540 2 Problem 3 LAN s are great but We want to connect them together...across the world Inter-networking 4 Internet Protocol (IP) Routing The Internet Multicast* Multi-protocol
CSE 565 Computer Security Fall 2018
CSE 565 Computer Security Fall 2018 Lecture 18: Network Attacks Department of Computer Science and Engineering University at Buffalo 1 Lecture Overview Network attacks denial-of-service (DoS) attacks SYN
Review of Internet Architecture and Protocols
Review of Internet Architecture and Protocols Professor Guevara Noubir Northeastern University noubir@ccs.neu.edu Lecture Reference Textbook: (source of some diagrams) Computer Networks: A Systems Approach,
Lecture 3: Packet Forwarding
Lecture 3: Packet Forwarding CSE 222A: Computer Communication Networks Alex C. Snoeren Thanks: Mike Freedman & Amin Vahdat Lecture 3 Overview Paper reviews Packet Forwarding IP Addressing Subnetting/CIDR
Internetworking - We are heterogeneity to our network (variable network technologies, bandwidth, MTU, latency, etc. etc.)
Internetworking - We are heterogeneity to our network (variable network technologies, bandwidth, MTU, latency, etc. etc.) Goal is to use this opportunity (and not to find the lowest common denominator
CS155b: E-Commerce. Lecture 3: Jan 16, How Does the Internet Work? Acknowledgements: S. Bradner and R. Wang
CS155b: E-Commerce Lecture 3: Jan 16, 2001 How Does the Internet Work? Acknowledgements: S. Bradner and R. Wang Internet Protocols Design Philosophy ordered set of goals 1. multiplexed utilization of existing
INTERNET SYSTEM. Internet Protocol. Kent State University Dept. of Computer Science. CS 4/55231 Internet Engineering. Large Scale Networking
CS 4/55231 Internet Engineering Kent State University Dept. of Computer Science LECT-6 SYSTEM 1 2 Large Scale Networking No Single Technology can Adequately Serve Every One s Need. Each LAN/ WAN has specific
Topics for This Week
Topics for This Week Routing Protocols in the Internet OSPF, BGP More on IP Fragmentation and Reassembly ICMP Readings Sections 5.6.4-5.6.5 1 Hierarchical Routing aggregate routers into regions, autonomous
CS 458 Internet Engineering Spring First Exam
CS 458 Internet Engineering Spring 2005 First Exam Instructions (read carefully): There are 6 problems for a total of 60 points. This is a closed book and closed notes in-class exam. If any problem is
Network Layer. The Network Layer. Contents Connection-Oriented and Connectionless Service. Recall:
Network Layer The Network Layer Recall: The network layer is responsible for the routing of packets The network layer is responsible for congestion control 1 2 Contents 4.1.1 Connection-Oriented and Connectionless
Network Layer. Recall: The network layer is responsible for the routing of packets The network layer is responsible for congestion control
The Network Layer 1 Network Layer Recall: The network layer is responsible for the routing of packets The network layer is responsible for congestion control 2 Contents Connection-Oriented (virtual circuit)
TSIN02 - Internetworking
Lecture 2: The Internet Protocol Literature: Forouzan: ch 4-9 and ch 27 2004 Image Coding Group, Linköpings Universitet Outline About the network layer Tasks Addressing Routing Protocols 2 Tasks of the
Network Layer: Internet Protocol
Network Layer: Internet Protocol Motivation Heterogeneity Scale Intering IP is the glue that connects heterogeneous s giving the illusion of a homogenous one. Salient Features Each host is identified by
COMP/ELEC 429/556 Introduction to Computer Networks
COMP/ELEC 429/556 Introduction to Computer Networks Let s Build a Scalable Global Network - IP Some slides used with permissions from Edward W. Knightly, T. S. Eugene Ng, Ion Stoica, Hui Zhang T. S. Eugene
ECPE / COMP 177 Fall Some slides from Kurose and Ross, Computer Networking, 5 th Edition
ECPE / COMP 177 Fall 2016 Some slides from Kurose and Ross, Computer Networking, 5 th Edition Course Organization Top-Down! Starting with Applications / App programming Then Transport Layer (TCP/UDP) Then
Lecture 11: Fragmentation & Addressing. CSE 123: Computer Networks Stefan Savage
Lecture 11: Fragmentation & Addressing CSE 123: Computer Networks Stefan Savage So what does IP do? Addressing Fragmentation E.g. FDDI s maximum packet is 4500 bytes while Ethernet is 1500 bytes, how to
IP: Addressing, ARP, Routing
IP: Addressing, ARP, Routing Network Protocols and Standards Autumn 2004-2005 Oct 21, 2004 CS573: Network Protocols and Standards 1 IPv4 IP Datagram Format IPv4 Addressing ARP and RARP IP Routing Basics
CSE/EE 461 Lecture 13 Connections and Fragmentation. TCP Connection Management
CSE/EE 461 Lecture 13 Connections and Fragmentation Tom Anderson tom@cs.washington.edu Peterson, Chapter 5.2 TCP Connection Management Setup assymetric 3-way handshake Transfer sliding window; data and
Administrivia CSC458 Lecture 4 Bridging LANs and IP. Last Time. This Time -- Switching (a.k.a. Bridging)
Administrivia CSC458 Lecture 4 Bridging LANs and IP Homework: # 1 due today # 2 out today and due in two weeks Readings: Chapters 3 and 4 Project: # 2 due next week Tutorial today: Joe Lim on project 2
IPv6 is Internet protocol version 6. Following are its distinctive features as compared to IPv4. Header format simplification Expanded routing and
INTERNET PROTOCOL VERSION 6 (IPv6) Introduction IPv6 is Internet protocol version 6. Following are its distinctive features as compared to IPv4. Header format simplification Expanded routing and addressing
Introduction to Networks and the Internet
Introduction to Networks and the Internet CMPE 80N Winter 2004 Lecture 18 Announcements Fourth quiz on Monday, March 1 st. Third HTML discussion session today by Kiran (before class). Summary posted on
CS 455 Internet Architecture, Page 3 ffl By 1985, the ARPANET was heavily used and congested; the National Science Foundation (NSF) initiated the NSFN
CS 455 Internet Architecture, Page 1 Network Layer, Part 3 Internet Architecture These slides are created by Dr. Yih Huang of George Mason University. Students registered in Dr. Huang's courses at GMU
IP : Internet Protocol
1/20 IP : Internet Protocol Surasak Sanguanpong nguan@ku.ac.th http://www.cpe.ku.ac.th/~nguan Last updated: July 30, 1999 Agenda 2/20 IP functions IP header format Routing architecture IP layer 3/20 defines
Communications Software. CSE 123b. CSE 123b. Spring Lecture 2: Internet architecture and. Internetworking. Stefan Savage
CSE 123b CSE 123b Communications Software Spring 2003 Lecture 2: Internet architecture and Internetworking Stefan Savage Some history 1968: DARPANET (precursor to Internet) Bob Taylor, Larry Roberts create
(Chapters 2 3 in Huitema) E7310/Internet basics/comnet 1
Introduction to routing in the Internet Ethernet, switching vs. routing Internet architecture IPv4 Addressing Routing principles Protocols: IPv4, ICMP, ARP (Chapters 2 3 in Huitema) E7310/Internet basics/comnet
The Interconnection Structure of. The Internet. EECC694 - Shaaban
The Internet Evolved from the ARPANET (the Advanced Research Projects Agency Network), a project funded by The U.S. Department of Defense (DOD) in 1969. ARPANET's purpose was to provide the U.S. Defense
Chapter 19 Network Layer: Logical Addressing
Chapter 19 Network Layer: Logical Addressing 19.1 Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 19.2 19-1 IPv4 ADDRESSES An IPv4 address is a 32-bit address
Security+ Guide to Network Security Fundamentals, Fourth Edition. Network Attacks Denial of service Attacks
Security+ Guide to Network Security Fundamentals, Fourth Edition Network Attacks Denial of service Attacks Introduction: What is DoS? DoS attack is an attempt (malicious or selfish) by an attacker to cause
Configuring IP Services
Configuring IP Services Last Updated: December 16, 2011 This module describes how to configure optional IP services. For a complete description of the IP services commands in this chapter, refer to the
Network Security. Evil ICMP, Careless TCP & Boring Security Analyses. Mohamed Sabt Univ Rennes, CNRS, IRISA Thursday, October 4th, 2018
Network Security Evil ICMP, Careless TCP & Boring Security Analyses Mohamed Sabt Univ Rennes, CNRS, IRISA Thursday, October 4th, 2018 Part I Internet Control Message Protocol (ICMP) Why ICMP No method
Packet Header Formats
A P P E N D I X C Packet Header Formats S nort rules use the protocol type field to distinguish among different protocols. Different header parts in packets are used to determine the type of protocol used
NetFlow Layer 2 and Security Monitoring Exports
The feature improves your ability to detect and analyze network threats such as denial of service (DoS) attacks by increasing the number of fields from which NetFlow can capture relevant data. NetFlow
Computer Network Fundamentals Spring Week 4 Network Layer Andreas Terzis
Computer Network Fundamentals Spring 2008 Week 4 Network Layer Andreas Terzis Outline Internet Protocol Service Model Addressing Original addressing scheme Subnetting CIDR Fragmentation ICMP Address Shortage
Network Security. Introduction to networks. Radboud University, The Netherlands. Autumn 2015
Network Security Introduction to networks Radboud University, The Netherlands Autumn 2015 What is a (computer) network Definition A computer network is two or more computers that are connected, so that
Computer Networks Principles Network Layer - IP
Computer Networks Principles Network Layer - IP Prof. Andrzej Duda duda@imag.fr http://duda.imag.fr 1 Network Layer Overview: Datagram service IP addresses Packet forwarding principles Details of IP 2
Lecture 2: Basic routing, ARP, and basic IP
Internetworking Lecture 2: Basic routing, ARP, and basic IP Literature: Forouzan, TCP/IP Protocol Suite: Ch 6-8 Basic Routing Delivery, Forwarding, and Routing of IP packets Connection-oriented vs Connectionless