Lecture #1 - Architecture Flashcards
Name the design principles of a mobile communication network
- All-IP Networks; circuit switch, packet switch
- Simple Network Architecture; 5G network structure
- Software Designed Control
- Cloud-ready
- Access-agnostic
- Multi-tenacy
- Integration, migration, network evolution
Name the main difference between connection-oriented and packet-based networks - what are the main benefits?
Circuit-switch/Connection-Oriented
- Long, continuous transmissions i.e. telephone
- One connection blocks resources (even if not used)
- High signaling overhead to control/set up connection
- User plane protocols are rather simple
- Quality of Service can be enforced
Packet-switched/Packet-based Network
- Burst-based communication
- Resources are shared/multiplexed between users
- Low complex control plane, higher complexity for user plane.
- No dedicated connection setup (but route planning)
- No Quality of Service guaranteed.
What’s Quality of Service (QoS)
What’s the difference between user plane and control plane.
User plane refers to all data forwarding processing within the network. The forwarding is controlled by the control plane.
The control plane controls the forwarding of data within the network - from source to sink. w
Explain software-defined networking/control
It involves the separation of control plane functions from the underlying hardware, allowing network operators to dynamically manage and configure their mobile networks through software interfaces.
Explain the set-up of a software defined control system.
- UE; smartphone
- Radio Access Network; CP + UP (hard to differentiate, need CP at base station, tracking mobile terminals)
- Core Network; seperate control and user plane entity (controlling packet and QoS mostly, policy enforcement)
- Self-Organising Networks
- Between long-term and short-term checks.
- Unusual number of handover within networks, handover failures, spectral effiency low.
- SON react to these and control the network.
- OAM
Define how a software defined control system is then implemented.
Explain the benefit of this.
A simple network structure has three things:
- Protocols/Control Plane
- Operating System
- Forwarding HW
With SDC, we can split these three elements.
There are five benefits:
- The applications at the top of the layer can be changed and developed
- Simplified network management
- Increased performance through ‘global’ view on network
- Better troubleshooting
- Quality of Service
Describe the open-flow that implements SDC
- Match; matches port
VLAN - ports virtually made
MAC - ethernet
- Action
- Forward to set of ports
- Encapsulate and forward to countroller
- Send to processing pipe
- Modify fields - Counter
Protocol that somebody is accessing the based; data matching rule by tracking. Forward the to the controller.
- Priority; order of processing rules
- Time-out; when does the rule expire
Explain:
- State monitoring
- Topology
- Route planning
- State Monitoring
- Check the health of the system
- Topology
- Recording which box is connected to the port of another box
- Port set-up correctly
- Good for big networks
- Route planning
- Which route is the shorted
- Start to programme router
E.g. One of the links is broken. This means that
Explain the basic principles of a virtualised/cloud-ready mobile communication system
- Can change forwarding services into smaller units.
- Network Function Virtualisation
- Don’t execute networks on dedicated hardware.
- Network function only executed on SW; flexibility and is not dedicated to a particular hardware. This was very expensive and very hard to renew your hardware over-time. Can just get HW off-the-shelf.
Name the benefits of a cloud-ready architecture.
- Network Functions HW
- Orchestration; allocation of resources to services. Using the standard API’s.
- Programmable; behaviour can be changed on the fly, in line with the SDN principle
- Scaling
- Automation
- Visibility; Resources and conductivity can be monitored to take corrective actions.
- Performance; optimise available resources.
- Multi-tenacy; same resources can be used within the same partners without the consequences.
Name and explain the requirements of a cloud-ready architecture.
- Portability; NF are decoupled from underlying layer
- Performance
- Elasticity; be able to scale up for more users in the network
- Resiliency; maintain network during a failure
- Security; authorisation and authentication, each function has their own role and controlled
- Service Continuity; after failure, service can continue. service side not affected at user
- Service Assurance
- Energy Efficiency; Should also scale properly
- Transition; allow transition systems with legacy.
Describe the main characteristics of a cloud-ready system.
- Network functions implemented in software
- Modularisation of network functions
- Virtualisation
- Common API’s between NF’s.
Explain the difference between vertical scaling and horizontal scaling
Vertical Scaling
1. Increase resources
2. Single point of failure
Horizontal Scaling
1. Add additional servers
2. Load balancing and ordchestration
3. More complex
Explain the difference between traditional, IaaS, PaaS, SaaS
Traditional; everything is maintained by the user
Infrastracture as a Service; the virtualisation layer and networking, storage and compute is managed by user. Means then, updates and stuff is managed by user.
Platform as a Service; Allows a platform, which allows multi-tenacy. All that needs to happen is to add the applications and data. Implement your own logic; how session management is run
Software as a Service; Use applications running as a cloud (Microsoft Word).
