Explaining Application Services

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Goals

• Explain the importance of time synchronization and the role of NTP
• Explain the use of web, file/print, and database services
• Explain the use of email and voice services
• Explain how high availability services are provisioned using redundancy and load balancing

Where DHCP and DNS support basic network operations, other Application layer protocols provide platforms for user-level services, such as websites, databases, file/printer sharing, email, and voice/video calling.

Application Security and Time Synchronization

• Transport Layer Security (TLS)
• Network Time Protocol (NTP)
• Precision Time Protocol (PTP)

Web, File, Print, and Database Services

• services that form part of the TCP/IP protocol suite are mostly client-server protocols and applications

• client-server applications are based around a centralized server that stores information and waits for requests from clients

• HyperText Transfer Protocol (HTTP)

• Web Servers

• HyperText Transfer Protocol Secure (HTTPS)

• File Transfer Protocol (FTP)

• Secure File Transfer Protocol (SFTP)

• Server Message Block (SMB)

• Network Attached Storage (NAS)

• Database Services

Email and Voice Servers

• Simple Mail Transfer Protocol (SMTP)
• Internet Message Access Protocol (IMAP)
• Voice and Video Services
• VoIP Protocols
• VoIP Phones

Disaster Recovery and High Availability

• Disaster Recovery Plan (DRP)
• Business Continuity Plan (BCP)
• Disaster Recovery Metrics
• Disaster Recovery Sites
• Fault Tolerance and Redundancy
• Load Balancers
• High Availability Clusters
• First-Hop Redundancy Protocols (FHRP)