Network Applications Flashcards
1
Q
HTTP
A
Hypertext Transfer Protocol
- Enables clients (typically browsers) to request resources from HTTP server on port 80 by default
- Requests resource with URL (uniform resource locator)
- Server responds with either datea or error message
- Data sent unencrypted and no authentication from client or server
2
Q
HTTP Header
A
- Defines the formats of the responses and requests to and from HTTP servers
- Payload is usually HTML (Hypertext Markup Language).
3
Q
Web Servers
A
- HTTP Servers connected to the internet and hosting websites
- Main platforms are Microsoft Internet Information Server (IIS), Apache and nginx
4
Q
Dedicated Server
A
- Private HTTP server allocated by rented as service from ISP
- Typically unmanaged or management has an additional cost
5
Q
VPS
A
Virtual Private Server
- ISP Allocated VM within a physical server
- Isolated by a hypervisor
6
Q
Cloud Hosting (HTTP Server)
A
- Website runs on cloud on several hardware computers, allowing more scalability if needed
7
Q
Shared Hosting (HTTP Server)
A
- Website is hosted within private directory on shared server
- Performance can be affected by other sites hosted on server because they all share resources
8
Q
SSL/TLS
A
Secure Sockets Layer/ Transport Layer Security
- Developed to address security problems with HTTP
- Encrypts TCP connections
- When used with HTTP is called HTTP Secure (HTTPS)
9
Q
HTTPS
A
HTTP Secure
- Web server is installed with digital certificate from certificate authority (CA)
- Proves identity of server, assuming client also trusts CA
- Certificate is wrapper for public/private encryption key pair
- Server and client use certificate to set up an encrypted tunnel
- Sent of port 443
10
Q
FTP
A
File Transfer Protocol
- Used to perform administrative upload/downloads for servers and appliances
- Port 21 used for commands and status, but not to transfer data
11
Q
Active FTP
A
- Client sends PORT command specifying chosen data connection port
- Server opens a connection between client port and port 20 on the server
- Poses issues for some firewalls, as the server is initiating inbound connection
12
Q
Passive FTP
A
- Client opens data port
- Sends PASV command to server control port
- Server opens random high number port and sends to the client with PORT command
13
Q
TFTP
A
Trivial File Transfer Protocol
- Connectionless, running over UDP port 69
- Not guaranteed delivery
- Only suitable for small files
- Only supports reading (GET) and writing(PUT) files.
- Most commonly used by legacy network applications.
- No security mechanisms
14
Q
SFTP
A
Secure FTP
- Encrypted authentication and data transfer between client and server
- Secure link is created using SSH over TCP port 22
- Command and data can then be sent over link without risk
- Requires an SSH server that support SFTPs
15
Q
Explicit TLS (FTPES)
A
- Means of securing FTP over SSL/TLS
- Use AUTH TLS to upgrade insecure connection over port 21 to secure one.
- This protects authentication credentials
- Data connection can be encrypted using PROT command
16
Q
Implicit TLS (FTPS)
A
- Negotiates SSL/TLS tunnel before exchange of FTP commands
- Uses Port 990
- Tricky to use with firewall
17
Q
SMB
A
Server Message Block
- Provides File/Print Sharing Services over windows network
- Allows hows to share directories and printers to other machines.
- Typically run over Port 445
18
Q
Port 9100
A
- Referred to as standard TCP/IP port, Appsocket, or JetDirect
- Establishes TCP connection to transfer raw Page Description Language (PDL) and Printer Job Language (PJL)
- Most common PDLs are PS and PCL
19
Q
IPP
A
Internet Printing Protocol
- Adapted form of HTTP that uses port 631 and can be implemented as secure protocol (IPPS)
- Provides better support for status messaging than port 9100
20
Q
WSD/AirPrint
A
- Allow device to advertise service capabilities over network
- Windows and Mac hosts can add device using play and play and manage it with status updates
21
Q
SQL
A
Structured Query Language
- Used to operate relational databases
22
Q
SMTP
A
Simple Mail Transfer Protocol
- Specifies how mail is delivered from one system to another.
- Server SMTP server finds IP of recipient server using domain name of recipient email address
- Recipient servers are registered in DNS for MX and A records
- Tries to send message several times and delivers non-delivery report(NDR if it failed.
23
Q
SMTPS
A
Secure SMTP
- Works much like HTTPS with certificate on server and negotiations between client and server
24
Q
Port 25
A
- Used to relay messages between SMTP servers
- If security is required STARTTLS command can be used to set up secure connection
25
Q
Port 587
A
- Used by mail clients to submit messages for delivery by SMTP server
- Servers configured for 587 should use STARTTLES and require authentication to send
26
Q
POP
A
Port Office Protocol
- Allows user client email software to access mailbox server
- Establishes connection to POP server on port 110
- User is authenticated and contents are downloaded to local PC
- Generally speaking, messages are deleted from mailbox server when they are downloaded
- Can be secured with TLS using port 995
27
Q
IMAP
A
Internet Mesage Acces Protocol
- Supports permanent connections to mailbox server and connecting multiple clients to mailbox at same time.
- Also allows client to manage mailbox on server
- Port 143.
- Secure TLS connection on port TCP/993
28
Q
POTS
A
Plain old telephone service
- Legacy, analog voice service
29
Q
PBX
A
Private Branch Exchange
- Automated switchboard allowing single connection point for orgs voice lines
- Provides full phone system functionality over digital digital trunk line
30
Q
SIP
A
Session Initiation Protocol
- One of most widely uses session control protocols
- SIP endpoints are end user device, like IP handsets or client server web conference software
- Each device or user is assigned unique SIP Uniform Resource Code
Example: SIP:jaime@515support.com
Runs over UDP 5060 unsecured and 5061 secured.
31
Q
RTP
A
Real-time Transport Protocol
- Manages delivery of data in real time
- Uses UDP, but with some of the reliability features of TCP
- Works closely with RTP Control Protocol
- RTCP monitors session and send quality reports which can be used to modify session and aid QoS
32
Q
VoIP Phones
A
- Use VLAN tagging to ensure SIP control and RTP media protocols can be segregated from normal traffic.
33
Q
Main Web Server Platforms
A
- Apache, Microsft Internet Information Server(IIS) and nginx
