Overview of TCP/IP Applications
TFTP packet types
- Read request (RRQ) opcode 1 - Write request (WRQ) opcode 2 - Data (DATA) opcode 3 - Acknowledgment (ACK) opcode 4 - Error (ERROR) opcode 5
TCP/IP includes three major components
-Networks, when taken collectively, are referred to as the Internet. -Entire suites of protocols, software, and applications that are standard parts of many operating systems (OS), such as file transfer protocol (FTP) and hypertext transfer protocol (HTTP). -Actual networking protocols such as transmission control protocol (TCP), user datagram protocol (UDP), address resolution protocol (ARP), and Internet protocol (IP).
Manual allocation
A network administrator manually matchs the host's MAC-to-IP address in the DHCP database, just like BOOTP. DHCP simply passes this information to the client.
A long-haul network funded by the ARPA (later DARPA) and built by Bolt, Beranek, and Newman, Inc. From 1969 through 1990, ARPANET served as the basis for early networking research, as well as a central backbone during development of the Internet.
Advanced Research Projects Agency Network (ARPANET)
One of the most widely used codes for representing text in computers. ASCII codes represent letters, numerals, punctuation, and keyboard characters as numbers. For example, when the character "A" is pressed on the keyboard, the ASCII binary representation of that character is 100 0001 (hexadecimal 41). The basic ASCII character set uses 7 bits to represent the 128 text and keyboard elements.
American Standard Code for Information Interchange (ASCII)
Has several definitions, depending on the content. In database management, attribute refers to a property inherent in an entity or associated with that entity for database purposes. In the context of network management, an attribute is a property of a managed object that has a value. In Hypertext Markup Language (HTML) tags, an attribute distinguishes one similar element from another.
Attribute
An encoding method used to enable Simple Mail Transfer Protocol (SMTP) to represent non-textual binary attachments, such as graphics files or word-processed documents, as Multipurpose Internet Mail Extensions (MIME) extensions to American Standard Code for Information Interchange (ASCI)I text based email message.
Base64
A 2-byte field used to designate each consecutive 512 byte-long block of data transferred. The first block starts at one, then increments by one for each new block transferred.
Block #
How does the Domain Name System (DNS) resolve fully qualified domain names (FQDN) to IP addresses?
By looking up the names in an address mapping database.
Which file transfer protocol (FTP) command allows you to change directories within a file listing?
CD
Which three of the following are common Telnet application uses? (Choose three.)
Connect to an online database Connect remotely to run a specific application Connect to a router for network information
provides for automated host addressing. maintains dynamic mappings, handed out to network hosts for a limited period, called a "lease time." provides network address information like BOOTP, and can pass DNS, TFTP, and Windows Internet Naming Service (WINS) server addresses as well.
Dynamic Host Configuration Protocol (DHCP)
Which protocol allows clients to locate and download IP addressing and configuration information on an automatically renewable (lease) basis?
Dynamic Host Configuration Protocol (DHCP).
allows for asynchronous communications across heterogeneous networks
The Error Code field is 2 bytes long, and contains the error value representing the error condition 0 - Not defined (See the included Error Message field.) 1 - File not found 2 - Access violation 3 - Disk full or allocation exceeded 4 - Illegal TFTP operation 5 - Unknown transfer ID 6 - File already exists 7 - No such user
Error Code
A net ASCII-formatted error message used to explain an error code
Error Message
If you want to locate a previously saved Uniform Resource Locator (URL) so that you can quickly return to it as needed, where on the browser toolbar would you look?
Favorites
used to move files between two computers.
File Transfer Protocol (FTP)
uses TCP at the Transport Layer. The operation and appearance are as if we used Telnet to connect to a remote computer. Instead of typing the usual system control commands, we make do with a short list of commands for directory listings and file transfers between computers.
File Transfer Protocol (FTP)
Which TCP/IP application allows us to transfer files either within a browser or at the command line?
File transfer protocol (FTP).
A variable-length field containing American Standard Code for Information Interchange (ASCII)-formatted bytes representing the filename to be uploaded or downloaded, sent in RRQ and WRQ packets
Filename
the Application Layer protocol of web browsers and servers.
HTTP
Which best describes why an hypertext transfer protocol (HTTP) server can handle multiple simultaneous connections?
HTTP is stateless, which means the server has no knowledge of previous connections after they are dropped.
The authoring language used to create documents for use on the web.
Hypertext Markup Language (HTML)
Which statement best describes Internet Message Access Protocol (IMAP)?
IMAP allows users to scan email headers and choose email messages to download from the email server.
You are a networking consultant for a major telecommunications firm. They ask you to help them resolve a hacked email problem. It seems that someone is intercepting emails between district offices and inserting pornographic pictures in place of legitimate email attachments. How might you resolve this problem for them?
Implement Secure Multipurpose Internet Mail Extension (S/MIME) encoding on all outbound email attachments.
A protocol used for retrieving email messages from a mail server. IMAP4 is a version of IMAP like Post Office Protocol version 3 (POP3), but it supports additional features such as allowing keyword searches in email messages while the messages remain on the mail server.
Internet Message Access Protocol (IMAP)
an email protocol that offers enhancements to POP3 for Internet message retrieval. allows users to create and manage mail folders over the network, scan message headers while they remain on the server, and download only those messages they choose.
Internet Message Access Protocol version 4 (IMAP4)
If a Dynamic Host Configuration Protocol (DHCP) client fails to renew its lease at the 50-percent point, what happens next?
It attempts to obtain a lease at 87.5-percent lease time.
A public domain graphic compression format that conforms to the Joint Photographic Experts Group (JPEG) standard for image compression. JPEG/JFIF files offer higher resolution, with up to 16.7 million colors, and are generally used in continuous-tone images such as photographs. However, JPEG/JFIF compression is lossy (some image information is lost), even at the highest quality setting.
JPEG File Interchange Format (JFIF)
An open standard that defines a method of compressing still images. See JPEG File Interchange Format (JFIF).
Joint Photographic Experts Group (JPEG)
A file transfer protocol (FTP) server administrator can control server access in which three ways? (Choose three.)
Make only portions of the drive visible Control read and write privileges Limit file access
Which three of the following are Dynamic Host Configuration Protocol (DHCP) address allocation mechanisms? (Choose three.)
Manual Automatic Dynamic
Which two of the following are examples of email programs? (Choose two.)
Microsoft Outlook UNIX Sendmail
A variable-length field containing the data transmission mode value, used by RRQ and WRQ packets to define one of three data formats for the requested transfer netascii (8bit ascii), octet (raw 8bit bytes), or mail (8bit ascii sent to a user)
Mode
A standard for compressing video to fewer bits for storage and transmission.
Motion Picture Experts Group (MPEG)
An extension of Simple Mail Transfer Protocol (SMTP) that supports the exchange of a wide variety of document files by means of an email system.
Multipurpose Internet Mail Extension (MIME)
used in conjunction with SMTP to support more than just standard ASCII text files. Binary information—Word processed documents or spreadsheets Graphic images—Graphic Interchange Format (GIF) or Joint Photographic Experts Group (JPEG) files Video—Moving Pictures Expert Group (MPEG) files Audio—Waveform Audio File (WAV) files
Multipurpose Internet Mail Extension (MIME)
A software system developed by Sytek and IBM that operates at the Session Layer of the Open Systems Interconnection reference model (OSI/RM). Applications can call NetBIOS routines to carry out functions such as data transfer across a local area network (LAN).
Network Basic Input/Output System (NetBIOS)
synchronizes computer system clocks to coordinated universal time (UTC) over packet switched networks using IP on the Network Layer.
Network Time Protocol (NTP)
Began as an abstract model for data communications. The seven-layer OSI model falls logically into two parts. Layers 1 through 4, the "lower" layers, are concerned with the communication of raw data. Layers 5 through 7, the "higher" layers, are concerned with the networking of applications.
Open Systems Interconnection reference model (OSI/RM)
the Internet standard protocol for transferring email messages from client to server or from mail server to mail server. defines a protocol and set of protocol processes to transfer email messages between mail systems; it does not define the programs used to store and retrieve mail messages
Simple Mail Transfer Protocol (SMTP)
The TCP/IP protocols used for mail delivery
Simple Mail Transfer Protocol (SMTP) Post Office Protocol (POP3) Internet Message Access Protocol version 4 (IMAP4)
Internet email uses which two protocols? (Choose two.)
Simple Mail Transfer Protocol (SMTP). Post Office Protocol version 3 (POP3).
used to run a program on a remote computer.
Telnet
Main Menu26of134 Which TCP/IP application allows a network user to remotely log on and manipulate a network device?
Telnet.
a protocol used by diskless workstations, SIP phones, and other network devices to locate a server and download IP addresses, subnet masks, default gateway addresses, TFTP server addresses, and additional configuration information from the server.
The Bootstrap Protocol (BOOTP)
Automatic allocation
The DHCP server assigns a permanent IP address to the client.
Dynamic allocation
The DHCP server dynamically assigns the client an IP address from a pool of addresses, and limits the time the client can use the assigned address. This time limit is referred to as the "address lease period." Most DHCP implementations use dynamic address allocation.
What happens when the browser application finishes downloading the files necessary to display a web page?
The browser and server drop the connections, and the browser maintains the page and its elements in memory.
As a result of issuing the file transfer protocol (FTP) DIR command, each file listing entry begins with a "-"; what does the "-" indicate?
The entries are files
For what purpose would you choose to run the Telnet application?
To configure a router.
For what application is file transfer protocol (FTP) an excellent choice?
To download large files.
a thin version of FTP. uses the connectionless user datagram protocol (UDP) at the Transport Layer. often used to download firmware or software upgrades to routers, switches, Internet protocol (IP) telephones, and other network devices.
Trivial File Transfer Protocol (TFTP)
takes a binary file such as a graphic or a Word document and converts it to American Standard Code for Information Interchange (ASCII) for transmission
UNIX-to-UNIX Encode or Decode - Uuencode/Uudecode
Converts binary attachments to text for transport within Simple Mail Transfer Protocol (SMTP) email messages. Uuencode converts binary attachments to 7-bit American Standard Code for Information Interchange(ASCII) text, viewable from within a standard text editor.
UNIX-to-UNIX encoding (Uuencode)
A set of protocols, databases, and related servers that work cooperatively to share newsgroup information on the Internet. Rather than limit messages to only the sender and recipient, as does email, Usenet makes messages available to the public. Usenet messages are transported using Network News Transfer Protocol (NNTP).
Usenet
Designates the type of Network Basic Input/Output System (NetBIOS) name resolution the client uses; WINS supports several different node types. For example, a client might broadcast for name resolution (B-node) or first broadcast, then directly request name resolution (M-node).
WINS (Windows Internet Naming Service) node type
Pronounced wave, this file is the Microsoft and IBM developed format for storing raw, uncompressed audio files.
Waveform Audio File (.WAV)
Which is the best reason to use the file transfer protocol (FTP) application?
When you need to pass large files over a slow connection
A Microsoft client/server application that resolves network computer host names to Internet protocol (IP) addresses. WINS works in conjunction with Dynamic Host Configuration Protocol (DHCP), where the WINS server maintains a dynamic database of host name-to-address mappings. Because DHCP clients may not maintain the same address over time, WINS works well for this application. Standard Domain Name System (DNS) supports only hosts with statically assigned IP addresses.
Windows Internet Naming Service (WINS)
The equivalent of a UNIX daemon. Windows services provide specific functions, such as enabling file sharing or automatic virus protection, and can start automatically on system startup, manually as directed by the user, or when scheduled to run at a specific time of the day.
Windows service
One reason HTTP servers can handle thousands, and perhaps millions, of requests per hour
because web connections are stateless. after the web browser downloads the requested document, picture, or media file, the web browser and server disconnect that session
A Lotus Development Corporation proprietary mail system. cc:Mail does not provide Internet mail access, and thus must use an email gateway to send and receive Simple Mail Transfer Protocol (SMTP) mail.
cc:Mail
Each country is assigned a two-letter ccTLD. The United States uses .us, and other countries have their own codes. The complete ccTLD listing can be found at https://icannwiki.org/Country_code_top-level_domain.
country code top-level domain (ccTLD)
A UNIX service that runs automatically at system startup, or on demand in response to a system event, is called a "daemon." UNIX (and Linux) systems run many daemons, including some to support basic operating system (OS) services, and some for user services, such as hypertext transfer protocol (HTTP) or file transfer protocol (FTP) services. The Microsoft Windows equivalent of a daemon is a service.
daemon
A digital code that can be embedded into a document to prove its authenticity. Digital signatures are an application of public-key encryption technology; the sender of a document uses a private encryption key to encrypt a text string or the digest of the message. Document recipients use the sender's public-encryption key to decrypt the signature and authenticate the sender.
digital signature
The low-level software that controls the operation of a computer and its peripheral devices. MS-DOS is the operating system (OS) that preceded Microsoft Windows.
disk operating system (DOS)
The complete Internet system name for a host or server. The FQDN includes the hostname and the domain name. An example of a FQDN is ken.ncti.com. Where ken is the hostname and ncti.com is the domain name.
fully qualified domain name (FQDN)
Provides easy access to computer programs and often hides details of a program from the user.
graphical user interface (GUI)
One graphic image formats used in Hypertext Markup Language (HTML). Others include Joint Photographic Experts Group (JPEG), Scalable Vector Graphics (SVG), Portable Network Graphics (PNG), etc. GIF files, the popular format for small, animated, or simple images, are limited to 256 colors, have a lower resolution than JPEG files, offer lossless compression, and can be made transparent for a popular type of borderless effect.
graphics interchange format (GIF)
A Simple Network Management Protocol (SNMP) database that lists information objects relevant to each managed object. A managed element's MIB includes its own information objects. The management application's MIB is a compilation of all the individual managed element's MIBs.
management information base (MIB)
Also known as dual key encryption or asymmetrical key encryption, is a cryptographic system that uses two mathematically related keys; one key is used to encrypt a message and the other is used to decrypt it. People who need to receive encrypted messages distribute their public keys but keep their private keys secret.
public-key encryption
The protocol a diskless computer uses at startup to find its Internet protocol (IP) address. The computer broadcasts a request that contains its physical hardware address, and a server responds by sending the computer its IP address. RARP takes its name and message format from the IP address resolution protocol (ARP)
reverse address resolution protocol (RARP)
A UNIX client/server Simple Mail Transfer Protocol (SMTP) email system, which is widely used on the Internet. Sendmail specifies user and delivery agents, and provides services such as message control, addressing and address conversion, and header transformation.
sendmail
In a UNIX system, the shell is the command interpreter. UNIX systems can operate in several different shells, including the Bourne shell, Korn shell, and C shell. Linux systems can also operate in several shells.
shell
A messaging technology in which an intermediate device receives and stores messages for later retrieval. Email is a store-and-forward technology.
store and forward
A Hypertext Markup Language (HTML) command inserted in a document that specifies how a web browser should format the document or a portion of the document.
tag
a terminal emulation program that provides remote login capability on a TCP/IP network. The look and operation are like working from an operating system's (OS) command prompt. has been replaced by secure shell (ssh) across public networks
telnet
A program that allows a local computer to connect to a remote computer and appear to be logged on to the remote computer as if it were local. Terminal emulation programs are often used to access mainframe computers and servers.
terminal emulation
HTTP (Hypertext Transfer Protocol)
the Application Layer protocol web browsers use to request and transmit documents between themselves and an HTTP server. Web browsers are the front-end client used to access HTTP servers by means of a network. HTTP servers are commonly referred to as web servers.
The Domain Name System (DNS) name space starts at the root level; this is where the domain authority distribution begins, and is designated by a "." (period). Initially, six TLDs were defined, located immediately below the root, to reflect current groups, as well as new groups who were adopting transmission control protocol/Internet protocol (TCP/IP) networks. These original domain names were .gov (government), .edu (education), .com (commercial), .mil (military), .org (organization), and .net (network service providers).
top-level domain (TLD)
The file transfer protocol (FTP) server process can run as which two of the following? (Choose two.)
Daemon Windows service
The Data field varies from 0 to 512 bytes in length, and contains a block of data. If the Data field in a packet is less than 512 bytes long, it signifies the last block in the transfer
Data
allows a user to find other computers using names instead of IP addresses. a mechanism to translate the alphanumeric fully qualified domain names (FQDN) we use in Internet Uniform Resource Locators (URL) to the IP addresses computers understand
Domain Name System (DNS)
To resolve fully qualified domain names (FQDN) to binary IP addresses, resolvers contact which type of TCP/IP application server?
Domain Name System (DNS).
Which two choices are examples of trivial file transfer protocol (TFTP) use? (Choose two.)
Download router upgrades. Software upgrades to IP telephones.
Which Dynamic Host Configuration Protocol (DHCP) network address allocation mechanism assigns a host a temporary IP address?
Dynamic
requests mail be downloaded for storage on the local client. stores the incoming email until the server authenticates a client mail application and downloads the messages to the client
Post Office Protocol (POP3)
used to transfer information from a mail server to a user's computer, so users can read, delete, or otherwise manage their email;
Post Office Protocol Version 3 (POP3)
Which two protocols deliver email directly to the email client? (Choose two.)
Post Office Protocol version 3 (POP3). Internet Message Access Protocol version 4 (IMAP4).
Of the five trivial file transfer protocol (TFTP) packet types, which three choices below are TFTP packet types? (Choose three.)
Read request Write request Acknowledgment
Gathers network information at a central workstation. RMON defines additional Simple Network Management Protocol (SNMP) management information bases (MIB) that provide more detailed information about network usage and status.
Remote Monitoring (RMON)
A software or hardware device installed in a network component, or attached to a network segment, designed to monitor the network and its devices. The probe sends information it has gathered to the network monitoring station.
Remote Monitoring (RMON) probe
Improves upon Remote Monitoring (RMON) by providing traffic data at the Network Layer in addition to the Physical Layer. This allows administrators to analyze traffic by protocol.
Remote Monitoring 2 (RMON2)
Why does Simple Mail Transfer Protocol (SMTP) need additional protocols to carry non-text data as attachments?
SMTP only carries ASCII text characters.
A Multipurpose Internet Mail Extensions (MIME) version that supports message encryption using public-key encryption technology. This ensures that email is sent and received in a manner that is secure from interception or tampering.
Secure MIME (S/MIME)
addresses the MIME standard's security shortcomings. defines methods that allow senders to encode email attachments in a manner that either ensures the attachment's authenticity or protect its contents.
Secure Multipurpose Internet Mail Extension (S/MIME)
