Types of Network Services

Database management systems (DBMS) extensively utilize various network services and protocols to enable communication, connectivity and data access across clients, servers, and heterogeneous systems. As database environments become more distributed and complex, the network services supporting DBMS architectures play an increasingly critical role.

Types of Network Services

Modern database systems are highly dependent on network services to provide seamless data access and management capabilities across distributed deployments. Services like file and print sharing, directory services, web protocols, virtual private networking, and distributed transaction management form the foundation of DBMS functions.

Understanding the key network services and how they support database connectivity and operations is essential for planning, configuring and managing networked database implementations. This article provides an in-depth overview of the major types of network services utilized in database environments.

Client/Server Model

The client/server model is one of the most common architectures used in database management systems. It separates the DBMS into two components:

• Database servers – These store the database and handle request processing, queries, updates, transaction management and data security.
• Clients – These are front-end software applications or devices that request data from the database server.

This separation of duties relies extensively on network services for communication between the clients and the database server:

• TCP/IP – Provides basic connectivity and transport between clients and database servers on local area networks or over the internet. TCP/IP is fundamental for allowing remote access to centralized databases.
• SQL – The Structured Query Language enables clients to submit database queries, updates and commands which are processed by the database server. SQL provides a standard interface over the network.
• ODBC/JDBC – Open Database Connectivity (ODBC) and Java Database Connectivity (JDBC) are application programming interfaces that allow more consistent database access between clients and servers across different DBMS platforms.
• Virtual Private Networking – Encrypted VPN tunnels securely connect remote clients to database servers over the public internet. This facilitates remote work and cloud database access.

Database Replication

Database replication copies data from one database server to other servers across a network to improve redundancy, reliability and performance:

• Transactional Replication – Real-time copying of database modifications between servers. Relies on services like Microsoft Distributed Transaction Coordinator (MSDTC) for synchronized transaction handling.
• Merge Replication – Asynchronous copying of data between servers on separate schedules. Utilizes file transfer protocols like FTP.
• Snapshot Replication – Periodic complete copies of database contents between servers. Leverages file sharing services like SMB and NFS.
• Replication Monitoring – Tracking status and troubleshooting replication issues depends on connectivity to database servers from centralized consoles and logging.

High Availability

High availability architectures reduce downtime by distributing database workloads across clustered servers that can failover quickly if an outage occurs:

• Load Balancing – Spreading requests across multiple servers. Achieved via dedicated load balancer appliances or DNS round robin routing.
• Failover Clustering – If the primary database server goes down, clustered secondary servers automatically take over processing. Requires shared storage over Fibre Channel or iSCSI.
• Synchronous Replication – Constant data mirroring between clustered servers for rapid failover. Depends on very low latency, high throughput storage networks.

Web Access

Web-based access to databases from browser applications or mobile apps is enabled by:

• HTTP – Hypertext Transfer Protocol provides connectivity between web clients and database web servers. HTTPS adds encryption through SSL/TLS.
• APIs – Application programming interfaces like REST, SOAP and OData enable databases to receive and send XML or JSON data over HTTP web requests.
• Web Application Servers – Server software like Node.js, Tomcat and IIS handle client web requests and interface with the DBMS backend.
• Push Notifications – Services like Firebase Cloud Messaging allow database servers to proactively push data updates to web and mobile clients in real time.

Cloud Database Services

Public cloud platforms offer fully managed database services. These leverage the provider’s network to offer benefits like global access, scaling, and redundancy:

• Object Storage – Unstructured data stored in cloud storage “buckets” that can be accessed from database servers. Utilizes REST APIs over HTTP.
• Load Balancers – Distribute queries across multiple database server instances. Alleviates bottlenecks and improves performance.
• Virtual Private Cloud – Isolates cloud databases in a private network while allowing authorized remote access over the internet VPN or dedicated links.
• Auto Scaling – Database capacity can be programmatically scaled out or in based on parameters like CPU utilization.

Monitoring and Administration

Administering database environments depends heavily on network services:

• Secure Shell (SSH) – Encrypted remote command line access to administer both local and remote database servers.
• Simple Network Management Protocol (SNMP) – Network devices can be monitored and managed by pulling data from SNMP agents over UDP.
• Logging – Database log files can be consolidated to centralized logging servers like Elastic, Splunk or Graylog for analysis and troubleshooting.
• Virtual Network Computing (VNC) – Graphical remote access to database servers for visual administration and monitoring.

Directory Services

Centralized directories containing user accounts and permissions are critical for secure database access control:

• Lightweight Directory Access Protocol (LDAP) – LDAP servers provide authentication services to DBMS servers and propagate access policies.
• Microsoft Active Directory – Widely used for storing users, groups and access rules that are referenced across an organization’s database infrastructure.
• Single Sign-On (SSO) – Central SSO servers allow users to authenticate once and seamlessly access multiple databases without re-logging in.

Conclusion

Network services form the backbone of how modern database environments interconnect clients, servers, applications, services and platforms across networks. As blockchain, edge computing, hybrid cloud and other trends drive databases towards more distribution, the network services facilitating location transparency and decentralized orchestration will only increase in importance.

Mastering foundational network services like TCP/IP, cloud virtualization, high availability clustering, web protocols, directories and monitoring tools is mandatory for database administrators and architects seeking to effectively create, manage and optimize distributed database management systems.

FAQ’s on Types of Network Services

1. How do network services enable DBMS functionality?

Network services like TCP/IP, virtual private networking, load balancing, and remote access protocols allow DBMSs to operate in distributed environments across multiple servers and locations. They facilitate key capabilities like database replication, high availability, web access, and centralized administration.

2. What is database replication and why are network services important for it?

Database replication copies data from one database server to other servers across a network. This provides redundancy, better performance, and geographic distribution. Network services like file sharing, transaction coordination, and data synchronization enable different types of database replication.

3. What network protocols help enable web access to databases?

Key protocols that allow web browser and mobile access to databases include HTTP/HTTPS, web APIs like REST and SOAP, web application servers, and push notification services. These leverage basic TCP/IP networking to query and update databases remotely.

4. How do network services help improve database high availability?

High availability uses clustering, load balancing, failover, heartbeat monitoring, and synchronous replication across redundant network links to minimize database downtime and distribute workload.

5. What are some examples of client/server protocols used in DBMS?

Common protocols that connect database clients and servers include ODBC, JDBC, and native SQL client networking. TCP/IP provides basic connectivity.