Symposium 2005 DECnet-Plus und TCP/IP Evolution of DNA DNA Phases Phase I • DECUS IT - Symposium - 1976 PDP-11 RSX DECUS IT - Symposium - Program to program (task to task) communication - File Transfer 4. April - 8. April 2005 4. April - 8. April 2005 - Typical customer was NOT an end user - Maximum network size of 16 point-to-point nodes Düsseldorf Düsseldorf Phase II • - 1978 VAX 11/780 VMS V1, RSX, RT-11 - Remote file access - Viewing and listing directories - Network management - Maximum network size of 64 point-to-point nodes - Provided a means of monitoring, testing and controlling the network Karl Bruns Karl Bruns Phase III Trainer/Consultant • Trainer/Consultant - 1980 OpenVMS and Networking OpenVMS and Networking - Adaptive routing OSI, DECnet, X.25 and TCP/IP OSI, DECnet, X.25 and TCP/IP - Network terminals (e.g. SET HOST) Lessingstr. 1 - Multipoint lines Lessingstr. 1 D-86438 Kissing D-86438 Kissing - CCITT X.25 Phone +49/8233/2938 Phone +49/8233/2938 - Record access Mobile +49/1717168148 Mobile +49/1717168148 - Down-line loading www.kbruns-training.de www.kbruns-training.de - Maximum size of network was 255 nodes karl.bruns@web.de karl.bruns@web.de 1 2 Karl Bruns Karl Bruns Seite 1 ww.decus.de
Symposium 2005 What comprises Evolution of DNA DECnet-Plus ? • Phase IV - 1983 - Incorporated LAN technology into DECnet • DNA Phase IV, complete stack including - Ethernet-LANs DNA IV Applications • - LAT-Support, Terminalserver DNA IV Routing • - with VMS 4.0: VAXcluster DNA IV Datalinks (DDCMP etc.) - Token Ring Support for Q-Bus • - SNA-Gateway - Implementing OSI with separate Products: VOTS, OSAK, FTAM, • OSI (Complete Stack, Layers 1-7) X.400, ... OSI Applications (FTAM, VTP) - Maximum size of network ~64.000 nodes • OSI Transport (TP0, TP2, TP4) • • Phase V OSI Routing (ISO 8473, ISO 9542, ISO 10589) • - 1988 IBM announced SAA OSI Datalinks (ISO 8802.3, ISO 8802.2, ...) • Digital announced DNA Phase V with full support of the OSI CONS (X.25, ISO 8208, ISO 7776) OSI architecture model • NSAP max. 20 bytes - 1991 • DNA Phase IV Applications over TP4 VAX Extensions for VAX/VMS (Wave 1) VAX P.S.I. V5 still remaining NCP • DNA IV - OSI Interworking DECnet/OSI for Ultrix Phase IV Router with V Router • - 1992 DECnet/OSI Wave 2 Phase IV and V Router with IV and V End Systems • full NCL-Management - 1993 Wave 3 DNA IV applications over OSI Transport (TP4) • “DECnet over TCP/IP” DECnet/OSI for Digital UNIX - 1996 DECnet-Plus for OpenVMS V7.1 and Digital UNIX V4.0 3 4 Karl Bruns Karl Bruns Seite 2 ww.decus.de
Symposium 2005 The Double-Headed OSI Standards Monster Reference Model of Open Systems Interconnection D D C $ F X X X.25 E E M V T SNA D Q APPL T 5 4 ISO 7498-1 ISO 7498-2 ISO 7498-3 ISO 7498-4 C C A T ... 7 G E A I MGMT A 0 0 CCITT X.200 CCITT X.800 CCITT X.650 CCITT X.700 d d I P A R P O M 0 0 t n L P M ... Basic Reference Security Naming and Management s s OSI 6 OSI Presentation DNA Model Architecture Adressing Framework CDI Net Net DNA Session Control DECdns, .. Mgmt OSI Session 5 Mgmt CMIP NSP ISO TP 0, 2, 4 4 ISO 7498 describes: NCL 1. 7-layer-architectured-model (CLNS) (CONS) DECmcc 3 2. abstract description of the layers and services ISO Internet, IS-IS Routing and IS-ES X.25 PLP 3. Protocols of the layers (entities) LLC1 LLC2 Frame Layer 2 Ethernet Frame (LAPB) Token DQDB Ethernet FDDI DDCMP HDLC PPP V2.0 Relay Ring SMDS X.21, ISDN 802.3 1 802.5 802.6 X.21 bis 5 6 Karl Bruns Karl Bruns Seite 3 ww.decus.de
Symposium 2005 OSI Applications Network Layer over CONS OSI Application FTAM X.400 ... CLNS: ISO Internet Protocol 8473 • CONS: OSI Transport directly over X.25 PLP over X.25 frame layer or LLC2 • Null Internet OSI Presentation • Routing: IS-IS (Link State Routing LSR) • ES-IS DNA IV-routing (Routing Vector Routing (RVR) = Distance Vector Routing) Adaptive Routing OSI Session • Routing is based on costs (Metric) • ES = End System • IS = Intermediate System (Router) • L1-routing • OSI Transport L2-routing (area routing) • TP0, TP2 L1 L2 • RVR RVR RVR LSR LSR RVR X.25 packet layer LSR LSR most important rule: within an area only one algorithm • LLC2 X.25 frame layer 802.2 for mixed domains on L2: LAPB • Interphase links with static routes (Reachable Address Tables) Ethernet 802.3 MAN (DQDB) 802.6 X.21 FDDI 9314-x X.21bis ISDN 7 8 Karl Bruns Karl Bruns Seite 4 ww.decus.de
Symposium 2005 ES-IS Protocol IS-IS Protocol IS-IS PROTOCOL - ISO 10589 WITH EXTENSIONS The IS-IS protocol is supported by routers (IS) and not by end systems (ES). ISO 9542 - ES-IS PROTOCOL The original IS-IS protocol in DNA Phase V Routing was Digital proprietary. • The core of this original specification was taken as the base for ISO 10589 • Used in conjunction with ISO 8473 (ISO 9542 is meaningless without ISO 8473). ISO 10589 does not include multiprotocol routing, but has been extended by • Supported by all Phase V nodes. other specifications (for example, by RFC1195) to include integrated ISO 9542 supports automatic configuration of adjacent node addresses. multiprotocol routing. DNA Routing (Integrated IS-IS) is a superset of ISO 10589 • • End systems identify adjacent intermediate systems DNA Routing has been modified to ensure that implementations conform to ISO • 10589. • Intermediate systems (IS) identify adjacent end systems (ES) on LAN and WAN, and identify adjacent IS on WAN. The IS-IS protocol is used by intermediate systems (routers) to exchange information • about other nodes in the network - Adjacent IS on LAN are found by listening for IS-IS Hello be used. IS are informed of the existence of nonadjacent nodes • When an adjacent WAN IS is found, then IS-IS Hello will be used. • IS can determine the best (least cost) path to other nodes • IS informs ES of a better path. • Phase V routing algorithm • • ES can operate on a LAN, and without static tables. Link State Routing (LSR), same as that used in ISO 10589 • • ES can autoconfigure their area address from an adjacent IS. LSR defines the Phase V IS-IS messages (link state packets) to exchange, and • the algorithm to calculate the least cost path Only the following three extra message types are defined: Phase IV routing algorithm • - ES Hello Routing Vector Routing (RVR) • - IS Hello There is no ISO standard for this protocol (it is Digital proprietary) • - Redirect Defines different messages and algorithm • Supported by Phase V routers for interoperability with Phase IV routers • 9 10 Karl Bruns Karl Bruns Seite 5 ww.decus.de
Symposium 2005 Digital Router and IS-IS Protocol Gateway Products Hierarchical Routing: WANrouter 100/500 (not longer supported) • Phase V Routing is hierarchical (similar idea to Phase IV) A network may be divided into DECnet areas as follows: X25 Gateway (not longer supported) • Level 1 (L1) routers route messages within their own area. � Level 2 (L2) routers (known as area routers) can route messages from area to WANrouter 90 � • area. Level 2 routers also perform L1 routing within their own area WANrouter 250 � • On a Level 2 router it is possible to set a circuit to be L2 only. When this is � done, the circuit will only be used to route messages between L2 routers, DECnis 500/600 • and will not route to L1 routers or to ES. This is a new feature. DECbrouter 90 (Cisco) • RouteAbout-Family (Proteon) • with VMS 7.1: • host-based routing is back for VAX and AXP 11 12 Karl Bruns Karl Bruns Seite 6 ww.decus.de
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