Lesson-13: INTERNET ENABLED SYSTEMS NETWORK PROTOCOLS
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Ipsec, SSL, Firewall, Wireless Security
IPSec 1 Outline • Internet Protocol – IPv6 • IPSec – Security Association (SA) – IPSec Base Protocol (AH, ESP) – Encapsulation Mode (transport, tunnel) 2 IPv6 Header • Initial motivation: – 32-bit address space soon to be completely allocated. – Expands addresses to 128 bits • 430,000,000,000,000,000,000 for every square inch of earth’s surface! • Solves IPv4 problem of insufficient address space • Additional motivation: – header format helps speedy processing/forwarding – header changes to facilitate QoS IPv6 datagram format: – fixed-length 40 byte header – no fragmentation allowed 3 IPv6 Header (Cont) Priority: identify priority among datagrams in flow Flow Label: identify datagrams in same “flow.” (concept of“flow” not well defined). Next header: identify upper layer protocol for data 4 Other Changes from IPv4 • Checksum: removed entirely to reduce processing time at each hop • Options: allowed, but outside of header, indicated by “Next Header” field • ICMPv6: new version of ICMP – additional message types, e.g. “Packet Too Big” – multicast group management functions 5 IPv6 Security – IPsec mandated • IPsec is mandated in IPv6 – This means that all implementations (i.e. hosts, routers, etc) must have IPsec capability to be considered as IPv6-conformant • When (If?) IPv6 is in widespread use, this means that IPsec will be installed everywhere – At the moment, IPsec is more common in network devices (routers, etc) than user hosts, but this would change with IPsec • All hosts having IPsec => real end-to-end security possible 6 IPv6 Security • Enough IP addrs for every imaginable device + Real end-to-end security = Ability to securely communicate from anything to anything 7 IPv6 Security – harder to scan networks • With IPv4, it is easy to scan a network – With tools like nmap, can scan a typical subnet in a few minutes see: http://www.insecure.org/nmap/ – Returning list of active hosts and open ports – Many worms also operate by scanning • e.g. -
The Internet in Iot—OSI, TCP/IP, Ipv4, Ipv6 and Internet Routing
Chapter 2 The Internet in IoT—OSI, TCP/IP, IPv4, IPv6 and Internet Routing Reliable and efficient communication is considered one of the most complex tasks in large-scale networks. Nearly all data networks in use today are based on the Open Systems Interconnection (OSI) standard. The OSI model was introduced by the International Organization for Standardization (ISO), in 1984, to address this composite problem. ISO is a global federation of national standards organizations representing over 100 countries. The model is intended to describe and standardize the main communication functions of any telecommunication or computing system without regard to their underlying internal structure and technology. Its goal is the interoperability of diverse communication systems with standard protocols. The OSI is a conceptual model of how various components communicate in data-based networks. It uses “divide and conquer” concept to virtually break down network communication responsibilities into smaller functions, called layers, so they are easier to learn and develop. With well-defined standard interfaces between layers, OSI model supports modular engineering and multivendor interoperability. 2.1 The Open Systems Interconnection Model The OSI model consists of seven layers as shown in Fig. 2.1: physical (Layer 1), data link (Layer 2), network (Layer 3), transport (Layer 4), session (Layer 5), presentation (Layer 6), and application (Layer 7). Each layer provides some well-defined services to the adjacent layer further up or down the stack, although the distinction can become a bit less defined in Layers 6 and 7 with some services overlapping the two layers. • OSI Layer 7—Application Layer: Starting from the top, the application layer is an abstraction layer that specifies the shared protocols and interface methods used by hosts in a communications network. -
SILC-A SECURED INTERNET CHAT PROTOCOL Anindita Sinha1, Saugata Sinha2 Asst
ISSN (Print) : 2320 – 3765 ISSN (Online): 2278 – 8875 International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering Vol. 2, Issue 5, May 2013 SILC-A SECURED INTERNET CHAT PROTOCOL Anindita Sinha1, Saugata Sinha2 Asst. Prof, Dept. of ECE, Siliguri Institute of Technology, Sukna, Siliguri, West Bengal, India 1 Network Engineer, Network Dept, Ericsson Global India Ltd, India2 Abstract:-. The Secure Internet Live Conferencing (SILC) protocol, a new generation chat protocol provides full featured conferencing services, compared to any other chat protocol. Its main interesting point is security which has been described all through the paper. We have studied how encryption and authentication of the messages in the network achieves security. The security has been the primary goal of the SILC protocol and the protocol has been designed from the day one security in mind. In this paper we have studied about different keys which have been used to achieve security in the SILC protocol. The main function of SILC is to achieve SECURITY which is most important in any chat protocol. We also have studied different command for communication in chat protocols. Keywords: SILC protocol, IM, MIME, security I.INTRODUCTION SILC stands for “SECURE INTERNET LIVE CONFERENCING”. SILC is a secure communication platform, looks similar to IRC, first protocol & quickly gained the status of being the most popular chat on the net. The security is important feature in applications & protocols in contemporary network environment. It is not anymore enough to just provide services; they need to be secure services. The SILC protocol is a new generation chat protocol which provides full featured conferencing services; additionally it provides security by encrypting & authenticating the messages in the network. -
TCP/IP Standard Applications Telnet - SSH - FTP - SMTP - HTTP
TCP/IP Standard Applications Telnet - SSH - FTP - SMTP - HTTP Virtual Terminal, Secure Shell, File Transfer, Email, WWW Agenda • Telnet (Virtual Terminal) • SSH • FTP (File Transfer) • E-Mail and SMTP • WWW and HTTP © 2016, D.I. Lindner / D.I. Haas Telnet-SSH-FTP-SMTP-HTTP, v6.0 2 What is Telnet? • Telnet is a standard method to communicate with another Internet host • Telnet provides a standard interface for terminal devices and terminal-oriented processes through a network • using the Telnet protocol user on a local host can remote-login and execute commands on another distant host • Telnet employs a client-server model – a Telnet client "looks and feels" like a Terminal on a distant server – even today Telnet provides a text-based user interface © 2016, D.I. Lindner / D.I. Haas Telnet-SSH-FTP-SMTP-HTTP, v6.0 3 Local and Remote Terminals network local terminal workstation Host as remote terminal with Telnet Server with Telnet Client traditional configuration today's demand: remote login © 2016, D.I. Lindner / D.I. Haas Telnet-SSH-FTP-SMTP-HTTP, v6.0 4 About Telnet • Telnet was one of the first Internet applications – since the earliest demand was to connect terminals to hosts across networks • Telnet is one of the most popular Internet applications because – of its flexibility (checking E-Mails, etc.) – it does not waste much network resources – because Telnet clients are integrated in every UNIX environment (and other operating systems) © 2016, D.I. Lindner / D.I. Haas Telnet-SSH-FTP-SMTP-HTTP, v6.0 5 Telnet Basics • Telnet is connection oriented and uses the TCP protocol • clients connect to the "well-known" destination port 23 on the server side • protocol specification: RFC 854 • three main ideas: – concept of Network Virtual Terminals (NVTs) – principle of negotiated options – a symmetric view of terminals and (server-) processes © 2016, D.I. -
XEP-0347: Internet of Things - Discovery
XEP-0347: Internet of Things - Discovery Peter Waher mailto:peterwaher@hotmail:com xmpp:peter:waher@jabber:org http://www:linkedin:com/in/peterwaher Ronny Klauck mailto:rklauck@informatik:tu-cottbus:de xmpp:TBD http://www-rnks:informatik:tu-cottbus:de/~rklauck 2018-11-03 Version 0.5.1 Status Type Short Name Deferred Standards Track iot-discovery This specification describes an architecture based on the XMPP protocol whereby Things can be in- stalled and safely discovered by their owners and connected into networks of Things. Legal Copyright This XMPP Extension Protocol is copyright © 1999 – 2020 by the XMPP Standards Foundation (XSF). Permissions Permission is hereby granted, free of charge, to any person obtaining a copy of this specification (the ”Specification”), to make use of the Specification without restriction, including without limitation the rights to implement the Specification in a software program, deploy the Specification in a network service, and copy, modify, merge, publish, translate, distribute, sublicense, or sell copies of the Specifi- cation, and to permit persons to whom the Specification is furnished to do so, subject to the condition that the foregoing copyright notice and this permission notice shall be included in all copies or sub- stantial portions of the Specification. Unless separate permission is granted, modified works that are redistributed shall not contain misleading information regarding the authors, title, number, or pub- lisher of the Specification, and shall not claim endorsement of the modified works by the authors, any organization or project to which the authors belong, or the XMPP Standards Foundation. Warranty ## NOTE WELL: This Specification is provided on an ”AS IS” BASIS, WITHOUT WARRANTIES OR CONDI- TIONS OF ANY KIND, express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. -
Is QUIC a Better Choice Than TCP in the 5G Core Network Service Based Architecture?
DEGREE PROJECT IN INFORMATION AND COMMUNICATION TECHNOLOGY, SECOND CYCLE, 30 CREDITS STOCKHOLM, SWEDEN 2020 Is QUIC a Better Choice than TCP in the 5G Core Network Service Based Architecture? PETHRUS GÄRDBORN KTH ROYAL INSTITUTE OF TECHNOLOGY SCHOOL OF ELECTRICAL ENGINEERING AND COMPUTER SCIENCE Is QUIC a Better Choice than TCP in the 5G Core Network Service Based Architecture? PETHRUS GÄRDBORN Master in Communication Systems Date: November 22, 2020 Supervisor at KTH: Marco Chiesa Supervisor at Ericsson: Zaheduzzaman Sarker Examiner: Peter Sjödin School of Electrical Engineering and Computer Science Host company: Ericsson AB Swedish title: Är QUIC ett bättre val än TCP i 5G Core Network Service Based Architecture? iii Abstract The development of the 5G Cellular Network required a new 5G Core Network and has put higher requirements on its protocol stack. For decades, TCP has been the transport protocol of choice on the Internet. In recent years, major Internet players such as Google, Facebook and CloudFlare have opted to use the new QUIC transport protocol. The design assumptions of the Internet (best-effort delivery) differs from those of the Core Network. The aim of this study is to investigate whether QUIC’s benefits on the Internet will translate to the 5G Core Network Service Based Architecture. A testbed was set up to emulate traffic patterns between Network Functions. The results show that QUIC reduces average request latency to half of that of TCP, for a majority of cases, and doubles the throughput even under optimal network conditions with no packet loss and low (20 ms) RTT. Additionally, by measuring request start and end times “on the wire”, without taking into account QUIC’s shorter connection establishment, we believe the results indicate QUIC’s suitability also under the long-lived (standing) connection model. -
Well Known TCP and UDP Ports Used by Apple Software Products
Well known TCP and UDP ports used by Apple Languages English software products Symptoms Learn more about TCP and UDP ports used by Apple products, such as OS X, OS X Server, Apple Remote Desktop, and iCloud. Many of these are referred to as "well known" industry standard ports. Resolution About this table The Service or Protocol Name column lists services registered with the Internet Assigned Numbers Authority (http://www.iana.org/), except where noted as "unregistered use." The names of Apple products that use these services or protocols appear in the Used By/Additional Information column. The RFC column lists the number of the Request For Comment document that defines the particular service or protocol, which may be used for reference. RFC documents are maintained by RFC Editor (http://www.rfc- editor.org/). If multiple RFCs define a protocol, there may only be one listed here. This article is updated periodically and contains information that is available at time of publication. This document is intended as a quick reference and should not be regarded as comprehensive. Apple products listed in the table are the most commonly used examples, not a comprehensive list. For more information, review the Notes below the table. Tip: Some services may use two or more ports. It is recommend that once you've found an instance of a product in this list, search on the name (Command-F) and then repeat (Command-G) to locate all occurrences of the product. For example, VPN service may use up to four diferent ports: 500, 1701, 1723, and 4500. -
Lecture: TCP/IP 2
TCP/IP- Lecture 2 [email protected] How TCP/IP Works • The four-layer model is a common model for describing TCP/IP networking, but it isn’t the only model. • The ARPAnet model, for instance, as described in RFC 871, describes three layers: the Network Interface layer, the Host-to- Host layer, and the Process-Level/Applications layer. • Other descriptions of TCP/IP call for a five-layer model, with Physical and Data Link layers in place of the Network Access layer (to match OSI). Still other models might exclude either the Network Access or the Application layer, which are less uniform and harder to define than the intermediate layers. • The names of the layers also vary. The ARPAnet layer names still appear in some discussions of TCP/IP, and the Internet layer is sometimes called the Internetwork layer or the Network layer. [email protected] 2 [email protected] 3 TCP/IP Model • Network Access layer: Provides an interface with the physical network. Formats the data for the transmission medium and addresses data for the subnet based on physical hardware addresses. Provides error control for data delivered on the physical network. • Internet layer: Provides logical, hardware-independent addressing so that data can pass among subnets with different physical architectures. Provides routing to reduce traffic and support delivery across the internetwork. (The term internetwork refers to an interconnected, greater network of local area networks (LANs), such as what you find in a large company or on the Internet.) Relates physical addresses (used at the Network Access layer) to logical addresses. -
Internet Protocol Suite
InternetInternet ProtocolProtocol SuiteSuite Srinidhi Varadarajan InternetInternet ProtocolProtocol Suite:Suite: TransportTransport • TCP: Transmission Control Protocol • Byte stream transfer • Reliable, connection-oriented service • Point-to-point (one-to-one) service only • UDP: User Datagram Protocol • Unreliable (“best effort”) datagram service • Point-to-point, multicast (one-to-many), and • broadcast (one-to-all) InternetInternet ProtocolProtocol Suite:Suite: NetworkNetwork z IP: Internet Protocol – Unreliable service – Performs routing – Supported by routing protocols, • e.g. RIP, IS-IS, • OSPF, IGP, and BGP z ICMP: Internet Control Message Protocol – Used by IP (primarily) to exchange error and control messages with other nodes z IGMP: Internet Group Management Protocol – Used for controlling multicast (one-to-many transmission) for UDP datagrams InternetInternet ProtocolProtocol Suite:Suite: DataData LinkLink z ARP: Address Resolution Protocol – Translates from an IP (network) address to a network interface (hardware) address, e.g. IP address-to-Ethernet address or IP address-to- FDDI address z RARP: Reverse Address Resolution Protocol – Translates from a network interface (hardware) address to an IP (network) address AddressAddress ResolutionResolution ProtocolProtocol (ARP)(ARP) ARP Query What is the Ethernet Address of 130.245.20.2 Ethernet ARP Response IP Source 0A:03:23:65:09:FB IP Destination IP: 130.245.20.1 IP: 130.245.20.2 Ethernet: 0A:03:21:60:09:FA Ethernet: 0A:03:23:65:09:FB z Maps IP addresses to Ethernet Addresses -
The Internet Protocol, Version 4 (Ipv4)
Today’s Lecture I. IPv4 Overview The Internet Protocol, II. IP Fragmentation and Reassembly Version 4 (IPv4) III. IP and Routing IV. IPv4 Options Internet Protocols CSC / ECE 573 Fall, 2005 N.C. State University copyright 2005 Douglas S. Reeves 1 copyright 2005 Douglas S. Reeves 2 Internet Protocol v4 (RFC791) Functions • A universal intermediate layer • Routing IPv4 Overview • Fragmentation and reassembly copyright 2005 Douglas S. Reeves 3 copyright 2005 Douglas S. Reeves 4 “IP over Everything, Everything Over IP” IP = Basic Delivery Service • Everything over IP • IP over everything • Connectionless delivery simplifies router design – TCP, UDP – Dialup and operation – Appletalk – ISDN – Netbios • Unreliable, best-effort delivery. Packets may be… – SCSI – X.25 – ATM – Ethernet – lost (discarded) – X.25 – Wi-Fi – duplicated – SNA – FDDI – reordered – Sonet – ATM – Fibre Channel – Sonet – and/or corrupted – Frame Relay… – … – Remote Direct Memory Access – Ethernet • Even IP over IP! copyright 2005 Douglas S. Reeves 5 copyright 2005 Douglas S. Reeves 6 1 IPv4 Datagram Format IPv4 Header Contents 0 4 8 16 31 •Version (4 bits) header type of service • Functions version total length (in bytes) length (x4) prec | D T R C 0 •Header Length x4 (4) flags identification fragment offset (x8) 1. universal 0 DF MF s •Type of Service (8) e time-to-live (next) protocol t intermediate layer header checksum y b (hop count) identifier •Total Length (16) 0 2 2. routing source IP address •Identification (16) 3. fragmentation and destination IP address reassembly •Flags (3) s •Fragment Offset ×8 (13) e t 4. Options y IP options (if any) b •Time-to-Live (8) 0 4 ≤ •Protocol Identifier (8) s e t •Header Checksum (16) y b payload 5 •Source IP Address (32) 1 5 5 6 •Destination IP Address (32) ≤ •IP Options (≤ 320) copyright 2005 Douglas S. -
Opportunistic Keying As a Countermeasure to Pervasive Monitoring
Opportunistic Keying as a Countermeasure to Pervasive Monitoring Stephen Kent BBN Technologies Abstract This document was prepared as part of the IETF response to concerns about “pervasive monitoring” (PM) [Farrell-pm]. It begins by exploring terminology that has been used in IETF standards (and in academic publications) to describe encryption and key management techniques, with a focus on authentication and anonymity. Based on this analysis, it propose a new term, “opportunistic keying” to describe a goal for IETF security protocols, in response to PM. It reviews key management mechanisms used in IETF security protocol standards, also with respect to these properties. The document explores possible impediments to and potential adverse effects associated with deployment and use of techniques that would increase the use of encryption, even when keys are distributed in an unauthenticated manner. 1. What’s in a Name (for Encryption)? Recent discussions in the IETF about pervasive monitoring (PM) have suggested a desire to increase use of encryption, even when the encrypted communication is unauthenticated. The term “opportunistic encryption” has been suggested as a term to describe key management techniques in which authenticated encryption is the preferred outcome, unauthenticated encryption is an acceptable fallback, and plaintext (unencrypted) communication is an undesirable (but perhaps necessary) result. This mode of operation differs from the options commonly offered by many IETF security protocols, in which authenticated, encrypted communication is the desired outcome, but plaintext communication is the fallback. The term opportunistic encryption (OE) was coined by Michael Richardson in “Opportunistic Encryption using the Internet Key Exchange (IKE)” an Informational RFC [RFC4322]. -
61A Lecture 35 Distributed Computing Internet Protocol Transmission
Announcements • Homework 9 (6 pts) due Wednesday 11/26 @ 11:59pm ! Homework Party Monday 6pm-8pm in 2050 VLSB • Guest in live lecture, TA Soumya Basu, on Monday 11/24 • Optional Scheme recursive art contest due Monday 12/1 @ 11:59pm 61A Lecture 35 • No lecture on Wednesday 11/26 (turkey) • No lab on Tuesday 11/25 & Wednesday 11/26 • The week of 12/1: Homework 10 due Wednesday 12/3 & Quiz 3 due Thursday 12/4 on SQL Monday, November 24 ! The lab on SQL (12/2 & 12/3) will be an excellent place to get homework help 2 Distributed Computing A distributed computing application consists of multiple programs running on multiple computers that together coordinate to perform some task. • Computation is performed in parallel by many computers. • Information can be restricted to certain computers. • Redundancy and geographic diversity improve reliability. Distributed Computing Characteristics of distributed computing: • Computers are independent — they do not share memory. • Coordination is enabled by messages passed across a network. • Individual programs have differentiating roles. Distributed computing for large-scale data processing: • Databases respond to queries over a network. • Data sets can be partitioned across multiple machines (next lecture). 4 Network Messages Computers communicate via messages: sequences of bytes transmitted over a network. Messages can serve many purposes: • Send data to another computer • Request data from another computer • Instruct a program to call a function on some arguments. Internet Protocol • Transfer a program to be executed by another computer. Messages conform to a message protocol adopted by both the sender (to encode the message) & receiver (to interpret the message).