Computer Networks

SSL can be configured at the server level, allowing each server in a domain to have its own SSL configuration for flexibility. Option A is incorrect because SSL is not limited to domain-level only. Option C incorrectly states cluster-level configuration. Option D is false because normal listen ports remain available.

SOAP can run over HTTP (or SMTP), and SSL/TLS can secure SOAP over HTTP. SAML is an identity framework that can work alongside SOAP for authentication and authorization. All three pairings are valid: SOAP uses HTTP as a transport protocol, SSL/TLS provides encryption for SOAP messages, and SAML integrates with SOAP for identity assertions. The combination of all three protocols is commonly used in enterprise web services.

SNMP, Telnet, and FTP are legacy protocols that transmit data in clear text (unencrypted). This makes them vulnerable to eavesdropping and man-in-the-middle attacks. Modern secure alternatives include SNMPv3, SSH, and SFTP/FTPS which encrypt traffic.

This question asks which statement is FALSE (all true except). FC-SW (switched fabric) is analogous to Ethernet switching, not token ring. Options A, B, and C are all true: WWNs are like MAC addresses (unique device IDs), FC port IDs are like IP addresses (assigned addresses for communication), and private FC-AL uses 8-bit addressing (limiting to 126 devices after addressing overhead). The question structure correctly identifies D as the false statement.

DNS servers publicly map domain names to IP addresses, revealing a network's structure and host information. Hackers can query DNS to discover subdomains, mail servers, and other hosts, providing reconnaissance for attacks. TCP/IP is a protocol, not a server. Telnet and SSL don't expose network topology like DNS does.

The Network layer (Layer 3) of the OSI model provides connectivity and path selection between host systems on separate networks. It handles routing, logical addressing (IP), and determines the best path for data to travel from source to destination across networks.

The Application layer (Layer 7) is the topmost OSI layer and provides network services directly to user applications outside the OSI model. It offers interfaces for applications to access network services like file transfer, email, and web browsing.

Encapsulation is the process of wrapping data with protocol information (headers) as it moves down the OSI layers. Each layer adds its own header (and trailer for Data Link layer) to the data, creating a protocol data unit (PDU) suitable for network transmission.

The OSI reference model consists of 7 layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application. Each layer has specific functions in network communication, from physical bit transmission (Layer 1) to application-level services (Layer 7).

Layer 3 of the OSI model is the Network layer, which handles routing, logical addressing, and path determination between different networks. The Physical layer (Layer 1) deals with raw bit transmission over media, Data Link (Layer 2) handles node-to-node transfer on the same network, and Transport (Layer 4) provides end-to-end reliability.

Layer 1 of the OSI model is the Physical layer, which defines the electrical, mechanical, and procedural specifications for transmitting raw bits over a physical medium (cables, wireless signals). It deals with physical connectors, voltage levels, and modulation techniques.

Layer 2 of the OSI model is the Data Link layer, responsible for node-to-node data transfer on the same network segment. It handles framing, physical addressing (MAC addresses), error detection, and media access control (via MAC sublayer and LLC sublayer).

Layer 4 of the OSI model is the Transport layer, which provides end-to-end communication services, including reliable data delivery, flow control, error recovery, and multiplexing through ports. Protocols like TCP and UDP operate at this layer.

The Transport layer (Layer 4) of the TCP/IP model handles quality-of-service issues including reliability through acknowledgments and retransmissions (TCP), flow control via sliding windows, and error correction through checksums. The Application layer provides user services, Internet layer handles routing, and Network Access layer deals with physical transmission.

The TCP/IP Application layer encompasses the top three layers of the OSI model: Application (providing user services), Presentation (data representation, encryption, compression), and Session (dialogue control, synchronization). Therefore, Session is the third layer.