1. Design Unit 26 Design a small or home office network
HND in Computing and Systems Development

2. Timeline Week Activity 1 10 LO2 Devices, Bandwidth, Users 2 11
LO2 Applications, Scaling, Security 3 12
Assignment 2 LO2 4 13
LO3 Device installation 5
Introduction 14
LO3 Network installation 6
LO1 Capacity 15
LO3 Testing 7
LO1 Usage 16
L04 User access, maintenance 8
LO1 Security 17
LO4 Improvements 9
Assignment 1 LO1 18
Assignment 3 LO3 & 4 (mostly witness)

3. Learning outcome 2 Be able to design small or home office networks
Devices: number of connected devices; anticipated participation
Bandwidth: average load; peak load; local Internet availability; cost constraint Communications plan from lesson 2
Users: quality expectations; concept of system growth
Applications: requirements eg security, quality of service
Communications: considerations eg suited to devices, suited to users, lifestyle preferences, commercial requirements
Scalable: considerations eg supporting device growth, supporting additional devices, bandwidth use trend change
Security: considerations eg addressing policy, device participation, firewall rules, encryption preference

4. LO2 Assessment criteria
2.1 Design a small or home office network solution to meet a given specification 2.2 Evaluate the design and analyse user feedback

5. Client – server model
Splits the computing workload between clients who request services from the service providers – the server
The server runs one or more server programs which share their resources with clients
The client does not share any of its resources
Clients therefore initiate communication sessions with servers which await incoming requests

6. SOHO (Small Office Home Office) client server

7. Microsoft Server roles
File server
Print server
Application server
Mail server
DNS server (Domain name system)
Domain control server
DHCP (Dynamic Host Configuration Protocol) server

8. File server Manage access to files for sharing
Set disk quotas for users
Index files for quick search
Centralised storage for backup

9. Print server Allows printers to be shared Manage printers centrally
Download printer drivers to clients
Simplified installation

10. Web server Serves web pages Runs web applications Hosts databases
Controls access

11. Mail server Retrieve emails for all users and store locally
Store and manage accounts
Transfer s to clients
Transfer s out from clients to web
Spam filtering

12. DNS server User friendly names for network resources
Host DNS databases for local name resolution (converting user friendly names to IP addresses)
Run nslookup to see this working
Automatically update DNS information

13. Domain control server Permits roaming (any user can use any computer)
Store Active Directory (Microsoft) data
Manages user logon processes and authentication
Assign and enforce security policies
Control access to files, programs, resources

14. DHCP server Allocates IP addresses to clients
Sets the following for each client:
default gateway – for internet access 
domain name  - for active directory login
name servers - to translate www names to IP addresses
time servers – retrieve accurate time
Saves administrator time and good for mobile devices used on different networks

15. Server hardware choices
Considerations:
Reliability
Processing power
Memory
Storage
Backup
Type

16. Reliability Dual power supplies Uninterruptible power supplies
Redundant fans
Failover Ethernet adapters
Memory “chip kill”

17. Processors Server processors Designed for 24/7 Lower voltage operation
Intel Xeon
AMD Opteron
Designed for 24/7
Lower voltage operation
Less heat dissipation
Therefore more reliable

18. Memory
2GB for the OS
Need to look at the applications and number of users – check system requirements
For instance 1GB of RAM will support 50 users of Moodle
Servers use registered (improved stability) and ECC (error correcting code) RAM

19. Storage RAID Storage size determined by applications
redundant array of independent disks
Arranges disks into a logical single unit with redundancy
Disk failures do not result in data loss
Arrays rebuilt automatically
Storage size determined by applications
Consider separate drives/arrays for OS and data
SATA or SAS interfaces
Different drives for SOHO, NAS, data centre

20. Backup External hard drives NAS Cloud
Cheap
Slow over USB, not off site
NAS
RAID in a box, fast over Ethernet
Not off site
Cloud
Offsite
Costly, slow
Best approach – a combination of hardware
Also need software

21. Type Mini tower – scalable? Tower – located in office, scalable
Rack – requires a rack to hold it
Blade – datacentre usage

22. Activity Specify the server configuration for MWS
Hardware
Software
Backup
Use the case study, communication plan and application requirements (especially CAD information from Tony King)