Architecture of Distributed Systems

Transcription

1 Architecture of Distributed Systems Example HW-A1 R. H. Mak

2 Ajax and Spring Framework taken from R.H. Mak 2IMN10-UML page

3 : a system for automated network virtualization in iaas cloud infrastructures Taken from: Local cloud site Remote cloud site external network #1 management network production network network id = 2 VLAN id = 6 eth0 eth0.6 br6 tap6 external network #2 Open connection tapx network id = 3 VLAN id = 15 eth0.15 br15 tap15 Open connection tapy Rudolf Mak TU/e Computer Science 12-Sep-17 2IMN10- HW example 2

4 Questions about the model 1. What building blocks (AEs) do you see? What do they represent? Are they conceptual (C) or physical (P)? 2. Same questions as 1, but now for connectors? 3. To which view(point)s does the model belong? 1. Motivate why, and identify corresponding stakeholders and their concerns. 4. Which of the following EFRs are addressed (Y + motivation N)? 1. Performance/scalability, 2. availability/reliability, 3. security, 4. maintainability, 5. other? 5. Is there a concept of distribution (Y + motivation N)? 6. Comment on the clarity/semantics of the diagram ( ) + motivation Keep you answers crisp! R.H. Mak 2IMN10-UML page

5 Building blocks (C P) Services, lifelines (C) Two scenarios (C) initialization update A global library (C) A software package (C P) Actors human (C) runtime environment (C) server (C P) R.H. Mak 2IMN10-UML page

6 Connectors (C P) All (C) Message, Method invocation Is_a relationships, to indicate special services Part-of relationships (black diamond arrows) Dependency relationship (uses) R.H. Mak 2IMN10-UML page

7 View concern stakeholder There are even some indications of a deployment view, since a technology is mentioned (jsx3.net), as are a runtime elements such as a server Development view : the class structure of some entities is shown which is of interest to programmers. Process view: system integrators, testers can see how the various parts interact. Developers (programmers) can see which class methods are used. Scenario: testers can run these to test interaction. Users can see how to interact with the system. Because of the latter, it can be argued that the model also belongs to the logical view. R.H. Mak 2IMN10-UML page

8 Extra-functional requirements (Y + motivation N) Security: N Availability & reliability: Y There are error methods exhibited Maintainability: Y Class structure is shown at a level useful for implementation and modification Performance and scalability: N R.H. Mak 2IMN10-UML page

9 Distribution, Clarity and Semantics ( ) + motivation Distribution (Y + motivation) /N: N Clarity/Semantics ( ) + motivation: A mix of a class diagram and a sequence diagram. So on the one hand, a lot of information crammed into a single model, but on the other hand this guarantees consistency between development and process view models. R.H. Mak 2IMN10-UML page

10 Building blocks (C P) Local cloud site Remote cloud site external network #1 management network production network network id = 2 VLAN id = 6 eth0 eth0.6 br6 tap6 external network #2 Open connection tapx network id = 3 VLAN id = 15 eth0.15 br15 tap15 Open connection tapy Building blocks: Sites, machines, gateways, bridges, network cards, networks (LAN, WAN) (all P) VLANs (C) controller process (C) Rudolf Mak TU/e Computer Science 12-Sep-17 2IMN10- HW example

11 Connectors (C P) Local cloud site Remote cloud site external network #1 management network production network network id = 2 VLAN id = 6 eth0 eth0.6 br6 tap6 external network #2 Open connection tapx network id = 3 VLAN id = 15 eth0.15 br15 tap15 Open connection tapy All (C) Inclusion/containment relations (production network in site, etc.) Bindings of network cards (NICs) to networks or bridges Open connections Rudolf Mak TU/e Computer Science 12-Sep-17 2IMN10- HW example

12 View concern stakeholder Local cloud site Remote cloud site external network #1 management network production network network id = 2 VLAN id = 6 eth0 eth0.6 br6 tap6 external network #2 Open connection tapx network id = 3 VLAN id = 15 eth0.15 br15 tap15 Open connection tapy Physical view, because we see devices and machines. Important for suppliers, system engineers and network operators and administrators who have to put the system together and operate it Logical view, because it gives an overview of intra- and inter-cloud network services. Useful for system acquirers and developers. It also indicates a management network, which is used for configuration of the network and therefore of interest to the network operators and administrators. Rudolf Mak TU/e Computer Science 2IMN10- HW example Sep-17

13 Extra-functional requirements (Y + motivation N) Local cloud site Remote cloud site external network #1 management network production network network id = 2 VLAN id = 6 eth0 eth0.6 br6 tap6 external network #2 Open connection tapx network id = 3 VLAN id = 15 eth0.15 br15 tap15 Open connection tapy Security: Y because VLANs isolate network traffic of various cloud tenants Availability & reliability, maintainability, performance & scalability: N Others: Operability and configurability, presence of a management network Rudolf Mak TU/e Computer Science 12-Sep-17 2IMN10- HW example

14 Distribution (Y + motivation N) Local cloud site Remote cloud site external network #1 management network production network network id = 2 VLAN id = 6 eth0 eth0.6 br6 tap6 external network #2 Open connection tapx network id = 3 VLAN id = 15 eth0.15 br15 tap15 Open connection tapy YES: Because we can see sites, bridges, multiple machines, multiple networks Rudolf Mak TU/e Computer Science 12-Sep-17 2IMN10- HW example

15 Clarity/Semantics ( ) + motivation Local cloud site Remote cloud site external network #1 production network network id = 2 VLAN id = 6 eth0 eth0.6 management network br6 tap6 external network #2 Open connection tapx -- network id = 3 VLAN id = 15 eth0.15 br15 tap15 Open connection tapy No clear drawing conventions Physical configuration clear, but not much context on the intended purpose, i.e., cloud tenants requiring their applications to run on isolated networks that have no interference from other applications, of the system. Therefore, VLANs have to be configured/deployed on a physical network. Rudolf Mak TU/e Computer Science 12-Sep-17 2IMN10- HW example