Geri Dön

Bir SNA / LU 6.2 uygulaması

An SNA / LU 6.2 application

  1. Tez No: 39349
  2. Yazar: BÜLENT ÇINARKAYA
  3. Danışmanlar: DOÇ.DR. FÜSUN TUNALI
  4. Tez Türü: Yüksek Lisans
  5. Konular: Bilgisayar Mühendisliği Bilimleri-Bilgisayar ve Kontrol, Computer Engineering and Computer Science and Control
  6. Anahtar Kelimeler: Belirtilmemiş.
  7. Yıl: 1992
  8. Dil: Türkçe
  9. Üniversite: İstanbul Teknik Üniversitesi
  10. Enstitü: Fen Bilimleri Enstitüsü
  11. Ana Bilim Dalı: Belirtilmemiş.
  12. Bilim Dalı: Belirtilmemiş.
  13. Sayfa Sayısı: 77

Özet

ÖZET Bu çalışmanın amacı iki uygulama programının SNA/LU 6.2 protokolü kullanılarak haberleşmesini sağlamaktır. Geliştirilen uygulama Türkiye'de yapılan ilk SNA/LU 6.2 uygulamasıdır. SNA, IBM' in 1974 yılında hazırladığı 7 katmanlı bir ağ mimarisidir. Bu mimari günümüze kadar pek çok kere geliştirilmiş ve IBM sistemlerinin bağlantısında yaygın olarak kullanılır duruma gelmiştir. Bugün pek çok üretici SNA ağlara katılmak için değişik düzeylerde SNA desteği vermektedir. SNA/LU 6.2 protokolü SNA modelinde uygulamalar arasında haberleşmeye olanak sağlayan yüksek düzeyli bir protokoldür. örnek olarak elektronik posta aktarım hizmeti veren bir uygulama programı geliştirilmiştir. Bu program üzerinde çalıştığı sistemden gelen postaları SNA/LU 6.2 protokolü ile diğer programa, diğer programdan aldığı postaları üzerinde çalıştığı sisteme aktarmaktadır. Alınan ve gönderilen postalardaki alıcı ve gönderici adresleri yerel sisteme ait olabileceği gibi başka sistemlere de ait olabilir. Böylelikle ağ üzerindeki her hangi bir düğüm ile posta alış verişi sağlanmış olur. Program BSMTP standartına uygun postalar üzerinde çalışmakla birlikte içerdiği modüller genel amaçlı dosya aktarımını da sağlamaktadır.

Özet (Çeviri)

SUMMARY AN SNA/LU 6.2 APPLICATION The aim of this thesis is to communicate two appli cations via SNA/LU 6.2 protocol. The realized applica tion is the first one developed on this subject in Tur key. SNA (Systems Network Architecture), proposed by IBM in 1974, is a design specification for the data communi cations-oriented facilities and functions that must be provided and performed to achieve a viable, efficient, reliable and cost-effective basis for distributed data processing and advanced teleprocessing applications. SNA is not a product. It is a design specification - an architectural blueprint - comprehensively and unambigu ously stating the data communication facilities and functions that need to be provided and performed by hardware or software products such as teleprocessing access methods, control programs for communication con trol units and terminal control units, intended for either operating within, or for supporting, a distributed data processing system. The current version of SNA - the fourth major revi sion to the original - and the products based on it represent a comprehensive, coherent, powerful, flexible and easily enhanced data communications strategy for distributed data processing or complex teleprocessing applications. The number of large and demonstrably successful, data communication environments realized through SNA-based products. SNA is not only the best known, but, in effect, the 'de facto' standard for data communication strategies. All discussions on other data communication architectures, eg the International Stan dards Organization's seven-layer Reference Model of Open Systems Interconnection, inevitably use SNA as the basis for comparison. Rumors are rife that European PTTs are to provide SNA-based public data communication environ ments. The question of what will unseat SNA is no longer debateds the fundamental question now posed when other data communication strategies are proffered is 'how does it interact with SNA ?'. Today there are more than 20000 SNA network on the world. ACP/VTAM (Advanced Communica tions Function for the Virtual Telecommunications Access Method) is the core of most current SNA implementations.The objective of SNA is to specify a data communica tions environment that provides for the efficient and reliable transfer of data between end users, irrespective of their physical configuration. SNA specifies this data communication environment in terms of a collection of uniquely addressable, functional entities, called 'Network Addressable Units (NAU), inter connected by the first three layers which are called Path Control Network. Three types of NAU are defined within SNA: i. System Services Control Point (SSCP) : Every SNA environment must contain at least one SSCP. SSCPs con trol and manage the resources that make up an SNA envi ronment. Thus, while in an environment with only one SSCP, all the resources will be controlled by it; in an environment with multiple SSCPs, each SSCP will control the resources of a particular portion of an environment. The set of resources controlled by an SSCP is re ferred to as the 'domain' of that SSCP. An SSCP will control the following: The physical configuration of all the resources within its domain. The addition or removal of resources to or from its domain, The activation and deactivation of resources within its domain, The establishment of communication paths be tween resources, for data transfer (and the disconnection of these paths when data transfer is complete), The testing of resources within its domain, The recovery of faulty resources, The system operators' interactions with the re sources of its domain. ii. Physical Unit (PU) : Several control functions need to be performed by data communications environment, to establish and maintain its physical configuration. The activation, deactivation and operation of communica tion-specific entities, such as data links, need to be controlled. Certain resources within the environment might need to be loaded with software from another re source before they can participate in data transfer operations. Diagnostic information, such as dumps, might be needed from a failed resource to facilitate its recov ery. Such physical configuration - related control -viii-functions - managing communications-specific physical entities and, where necessary, loading and dumping re sources - are performed by PUs. PUs are invariably implemented by software. Thus, a Physical Unit - in SNA terms - is a piece of software that controls physical entities and physical operations (not, contrary to expectations, a physically-tangible component such as communications control unit). iii. Logical Unit (LU) : End users interact with the SNA-defined communications environment via LUs. LUs can be thought of as communications ports that enable end users to access and the use resources of the SNA environ ment for data transfer. Before end user-to-end user communication can occur each end user must access the communications environment via an LU. End user-to-end user communication is then achieved by means of SNA-defined transactions between the LUs. An LU performs the necessary data transformation and data flow management functions that are needed to support end user-to-end user communications. So, an LU should be viewed as a set of functions that are invoked by an end user to enable it to communicate with other end user, rather then as a rigid interface to the environment. A formal, bilateral and temporary relationship must be established between two NAUs before they can partici pate in any form of dialogue. This relationship is referred to, in SNA, as a 'session'. The session is a fundamental and intrinsic concept of SNA-, all communica tions within an SNA environment are based on sessions, and a hierarchy of sessions between the various types of NAU exists to control the environment and the data commu nication operations between end users. A session consists of two 'half-sessions'; one in the primary and one in the secondary NAU. A half-session is the set of functions used by a NAU to provide the protocols needed to support the communications within a particular session. SNA specifies four types of session that can be established between NAUs which ares -ix-LU-LU sessions, SSCP-LU sessions, SSCP-PU sessions, SSCP-SSCP sessions. The following list gives the characteristics of the LU session types. LU types 1 through 4, and 7 describe a host program supporting a device with limited function. LU types 6.1 and 6.2 describe program-to-program communi cation protocols. LU 0 : These protocols are not de fined by SNA. It is up to the LUs communicating to implement a set of protocols. For example, the proto cols that VTAM uses to support non- SNA 3270 binary synchronous communi cation (BSC) terminals are LU 0 pro tocols. LU 1 : Applications use LU 1 proto cols to access non display I/O devic es such as printers and keyboard printer terminals. LU 2 : Applications use LU 2 proto cols to access display terminals with the IBM 3270 data stream. LU 3 s Applications use LU 3 proto cols to access printers with a subset of the IBM 3270 data stream. LU 4 : Applications use LU 4 proto cols to access terminal that are similar to LU 1 terminals, but have more functions. LU 6.1 : Applications use LU 6.1 pro tocols to communicate with other ap plications. These are the original protocols SNA defined for communica tion between applications. Only ap plications in a host processor can use LU 6.1 protocols. LU 6.2 : These are the highest-level application protocols currently de fined by SNA. They can be implement ed by programs running on non-host systems and by programmable hardware devices in the network. LU 6.2 -x-protocols present a higher-level in terface to applications. LU 7 : Applications use LU 7 proto cols to access a single display sta tion. LU 6.2 application programs are an important part of an SNA network. Their function in the network can be understood by comparing them to other logical units and their associated session types. LU 6.2 protocols control synchronous communication between peers. The idea of a peer implies that both of the points communicating have similar communication processing capability. Both points may not have equal processing power. A PC, for example, does not have the processing capabilities of a mainframe. Both points, however, are capable of fulfilling the basic communica tion functions of a type 6.2 LU. In order to accommodate LU 6.2 implementations on different processors, and different languages, SNA LU 6.2 architecture defines how applications request LU 6. 2 services in generic term. This generic interface is called an 'LU protocol boundary'. Protocol boundaries offered to user application programs are defined in terms of verbs. By using these verb functions, a program on one end of the network can initiate a transaction with another program or device on the network, send and receive data as required by transaction, and terminate the transac tion. All of this can be done without the program being aware of the configuration of the network or even of the SNA protocols used to establish connections and transmit data across the network. An SNA/LU 6.2 application is developed which pro vides e_mail services. This application receives mails from the system and sends them to another application via LU 6.2 protocol. The address inhabited in 'from' and 'sender' fields of the mails can be local or can be any address on the network. This implies that, mail exchange can be done between any two systems on the network. Although application works on BSMTP format mails, for the time being but it can serve as a general purpose file transfer facility. -xi-

Benzer Tezler

  1. Tez No

    311195

    Mini vida ankrajının kullanıldığı iki farklı en masse retraksiyon mekaniğinin etkilerinin karşılaştırılması

    Comparison of the effects two different en masse retraction mechanics used with mini screw anchorage

    CELAL GENÇ

    Doktora

    Türkçe

    Türkçe

    2011

    Diş HekimliğiDicle Üniversitesi

    Ortodonti Ana Bilim Dalı

    PROF. DR. JALEN DEVECİOĞLU KAMA

  2. Tez No

    14458

    Ege Üniversitesi Güneş Enerjisi Enstitüsü tarafından geliştirilen serada muz yetiştirilmesinde hava sıcaklıklarının optimizasyonunun araştırılması

    Research of optimization of air temperatures for raising the green house developed by Ege University sun-energy

    YILDIZ DOĞDU

    Yüksek Lisans

    Türkçe

    Türkçe

    1991

    ZiraatEge Üniversitesi

    PROF.DR. A. ŞEMİ AKSOY

  3. Tez No

    88707

    Diabetes mellituslu hastalarda, diabet eritrosit membranı Na+ -K+ ATPaz enzim aktivitesi, MDA, DHEAS ve lipidler üzerine etkisinin araştırılması

    An Investigation diabetic yaer's effect on erythrocyte membrane's Na+-K+ ATPase enzyme activity, MDA, DHEAS and lipids in diabetes mellitus patients

    CEMALETTİN DAĞLAR

    Tıpta Uzmanlık

    Türkçe

    Türkçe

    2000

    BiyokimyaSelçuk Üniversitesi

    Biyokimya Ana Bilim Dalı

    DOÇ. DR. MEHMET GÜRBİLEK

  4. Tez No

    57491

    SNA ağ yönetim sistemi

    Başlık çevirisi yok

    SELVİYE FERHATOĞLU

    Yüksek Lisans

    Türkçe

    Türkçe

    1996

    Bilgisayar Mühendisliği Bilimleri-Bilgisayar ve KontrolYıldız Teknik Üniversitesi

    Bilgisayar Mühendisliği Ana Bilim Dalı

    YRD. DOÇ. DR. TÜLAY TİNLİ

  5. Tez No

    292887

    202 no'lu Besni şer'i mahkeme sicillerinin 101-220 sayfalarının transkripsiyonu ve değerlendirilmesi

    Translation and evaluation of the pages between 101 and 220 of the 202th Besni (Behisni) Kaza?s kadi register

    HÜSEYİN EKİZ

    Yüksek Lisans

    Türkçe

    Türkçe

    2011

    TarihKahramanmaraş Sütçü İmam Üniversitesi

    Tarih Ana Bilim Dalı

    DOÇ. DR. MEMET YETİŞGİN

Geri Dön