CREST CPSA Exam Questions and Answers

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1 CREST CPSA Exam Questions and Answers

Name all OSI layers - ANSWER✅✅Application, Presentation, Session, Transport, Network, Data Link, Physical.Name all TCP/IP layers - ANSWER✅✅Application, Transport, internet, Network Access.Name Four TCP head flags - ANSWER✅✅ACK, FIN, SYN, URG, PSH, RST Which layer does HTTP protocl reside in the OSI model. - ANSWER✅✅Layer 7, Application.Which layer does Ethernet reside in the OSI model. - ANSWER✅✅Layer 2, Data link.Which Layer does IPv4 & IPv6 reside in TCP/IP model. - ANSWER✅✅Layer 4, transport.RFC 1918 addresses - ANSWER✅✅10.0.0.0 - 10.255.255.255 (10/8 prefix) 172.16.0.0 - 172.31.255.255 (172.16/12 prefix) 192.168.0.0 - 192.168.255.255 (192.168/16 prefix) Name the well know, registered and dynamic port ranges. - ANSWER✅✅Well Known(0- 1023), Registed(1024-49,151) & Dynamic(49,152-65,535) What is an ephemeral port? - ANSWER✅✅An ephemeral port is a short-lived transport protocol port for Internet Protocol (IP) communications. Can be used by both TCP & UDP.What does IANA stand for? - ANSWER✅✅Internet Assigned Numbers Authority Name 10 common ports and there protocols. - ANSWER✅✅FTP21, SSH22, DHCP67(C),

DHCP68(S), NTP123, MYSQL3306, RDP3389, HTTP80, HTTPS443, SMB445, KERBEROS88,

CHARGEN19(UDP), DNS53, TACAS49, WHOIS43, MSSQL1433, HIDDEN MSSQL2433. 1 / 2

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2 Name five network types. - ANSWER✅✅LAN, WAN, MAN, VLAN, WLAN, PAN.Name five network topologies - ANSWER✅✅Mesh, Ring, star, Tree, Bus.Name five common ethernet and FDDI cable types. - ANSWER✅✅100Base5, 10Base2, 10BaseT, 100Base-FL, 1000Base-T.What is WIFI the alias for? - ANSWER✅✅IEEE 802.11 What does VLAN stand for? - ANSWER✅✅Virtual Local Area Network How does VLAN work? - ANSWER✅✅Virtual Local Area Networks (VLANs) separate an existing physical network into multiple logical networks.Thus, each VLAN creates its own broadcast domain. Communication between two VLANs can only occur through a router that is connected to both.Name five common ICMP types. - ANSWER✅✅8-echo, 0-echo reply, 30-trace route, 5- redirect, 3-destination unreachable, 11, time execeed.What does ICMP stand for? - ANSWER✅✅Internet Control Message Protocol What does TTL stand for? - ANSWER✅✅Time to Live What is TTL? - ANSWER✅✅TTL is a hop count system, and each router decreases the TTL by

• Upon reaching 0, the packet is dropped. This way you don't have packets not reaching their

destination and clogging the network.OS TLL numbers? - ANSWER✅✅128 Windows, 64 linux, 255 solaris(kapp) What is Traceroute - ANSWER✅✅Traceroute is when you send a packet with a TTL value of 1 once it reaches the first router it will die sending a ICMP message to sender, at which point the sender can send another one with a value of 2 to see how far it will go. By doing this we can see

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