UNIT 4. Connecting to a Network & Sharing Resources

Transcription

1 U 4 onnecting to a etwork & haring esources onna arren

2 opics for this Unit ransmission ontrol Protocol (P)/ nternet Protocol (P) for wired and wireless networks he pen ystems nterconnection ti () model, P addressing, and firewall settings Permissions older sharing in indows Printer sharing onna arren

3 A seven layered reference model that serves as a guideline for how to build communication protocols Each layer represents the virtual communication between the corresponding layers on different machines Model (pen ystem nterconnect) onna arren

4 Layer 1 - Physical Provides the Electrical, mechanical, functional, and procedural hardware specifications to connect a device to the network EA/A standard 232-E /E standard esponsible for encoding electrical signals into a format that can be sent of the physical media used for sending or receiving data bits s, repeater, hubs and concentrators work at this level onna arren

5 Layer 2 - ata Link ranslates bits from the Physical layer and puts them into data frames and adds a header containing the hardware (MA) destination and source address Attaches a trailer using (yclic edundancy hecksum) error checking Provides sequencing numbers for frames Bridges and layer 2 switches work at this level onna arren

6 Layer 3 - etwork esponsible for finding the best route by which to send frames over a network ormats frames into packets and provides logical routing addresses and retransmission Provides segmentation and reassembly services for packets routing to physical media with a different packet size outers and Layer 3 switches work at this level onna arren

7 Layer 4 - ransport Actually sends the data to another machine esponsible for error checking and requests retransmission of data if errors are detected an segment and reassemble packets if needed to provide more efficient transmission Uses Logical Addressing onnection dentifier ransaction dentifier onnection ervices (flow control between end nodes) onna arren

8 Layer 5 - ession Establish, manage and terminate a connection called a session ession ontrol implex - a node is either a transmitter or a receiver but not both Half-uplex- only one node can transmit a with the node taking turns transmitting ull uplex - odes can transmit and receive simultaneously but need some form of flow control to prevent one node from sending data faster than the other node can receive it onna arren

9 Layer 6 - Presentation onverts and translates data for the adjacent layers Protocol conversion ata encryption and decryption ata compression and decompression edirectors and gateways work at this level onna arren

10 Layer - Application Provides a set of Application Program nterfaces that t provide communication between applications and the processes they request ontains protocols that provides common services needed by an application such as Electronic mail transport emote file access emote job execution etwork directory services etwork management onna arren

11 nstalling etwork upport efault networking components installed lient for Microsoft etworks Qo Packet cheduler ile and Printer haring for Microsoft etworks nternet Protocol Version 6 (P/Pv6) nternet Protocol Version 4 (P/Pv4) Link Layer opology iscovery / river and Link Layer opology iscovery esponder onna arren

12 ask List etwork and haring enter ummary etwork Map View Your Active etworks hange Your etworking ettings onna arren

13 etwork iscovery ontrols indows irewall settings Afi firewall llis a barrier between the computer and the network that allows certain types of traffic through, h and blocks other traffic irewalls filter using P/P characteristics P addresses Protocol numbers Port numbers onna arren

14 etwork iscovery ettings or ontrols two functions: 1. hether the computer can see and be seen by the other systems on the network 2. hether the computer can share its resources and access shared resources on the network onna arren

15 hanging g the etwork Location onna arren

16 Advanced haring onna arren

17 P/P Architecture onna arren

18 P/P onna arren

19 P versus MA Addresses P address (Logical) tructured address that contains both network and host information ritten in the decimal system 1-byte, 32-bit address MA address (Physical) lat address with no structure ritten in the hexadecimal number system 6-byte, 48-bit address onna arren

20 P/P Address Parameters P address - a unique 32 bit binary number expressed in dotted decimal notation ( ) ubnet mask - identifies which part of the P address identifies the network and which part identifies the node efault gateway address - identifies the router that will forward P traffic outside the local network onna arren

21 lass A B P Addresses ormats 0 et Host 10 et Host 110 et Host 1110 Multicast Address 8bits 8bits 8bits 8bits onna arren

22 Maximum Hosts by lass lass ubnets o. of Addresses lass A ,,216 lass B ,536 lass onna arren

23 Maximum Valid Hosts by lass lass ubnets o. of Addresses lass A ,,214 lass B ,534 lass onna arren

24 P Address eservations A network number cannot be all 0 s. t is interpreted to mean this network A host number cannot be all 0 s - this syntax refers to the network itself. Example refers to host on the current class B network he final octet cannot be all 1 s 1s or 0 s 0s (0 or 255) (255 is the broadcast address) he first octet t cannot be is the loop back address onna arren

25 ubnet Masks Each P class is paired with a mandatory default subnet mask he subnet mask designates which h portion of the address is the network number and which is the host 1 s indicate the network and 0 s indicate the host onna arren

26 efault ubnet Masks lass A lass B lass onna arren

27 Pv4 Addressing Parameters P Address 32 bit address in dotted decimal notation ( ) ubnet Mask ) efault Gateway Address address of the router on the network or subnet P Address - omain ame ervice is used to translate names like into an P Address ( ) onna arren

28 Automatic P/P onfiguration Uses HP ynamic Host onfiguration Protocol lients request and receive addressing information from HP an be a server or router onna arren

29 Manual P/P onfiguration Manually enter information into all fields in the P/P Properties dialog box epending on whether you are connected to other networks, you do not have to fill out all fields Minimum requirements: P Address ubnet Mask onna arren

30 Using etsh.exe yntax: netsh interface ipv4 set address connection_name static ip_address subnet_mask default_gateway An example of an actual command would be as follows: netsh interface ipv4 set address Local Area onnection static onna arren

31 reate a ew etwork onnection Local network connections are created automatically Manual connections frequently have to be made ial up connections onna arren

32 isplays a graphical map of the network configuration and all its components etwork Map etwork iscovery must be turned on f the computer is a member of a Active irectory domain, group policy must be configured to permit network mapping Any indows XP computers on the network must have the LL esponder software installed onna arren

33 indows etwork iagnostics Problems that can be diagnosed: Broken or detached cable connections P Address and ubnet Mask problems efault gateway problems and HP configuration problems etworking hardware configuration problems nternet server addresses and service settings onna arren

34 unning etwork iagnostics lick on warning icon on network map and indows etwork iagnostics launches Attempts to discover the cause of the problem and offers possible solutions onna arren

35 P/P ools onna arren

36 ipconfig isplay s the computer s P configuration :\> ipconfig /all (ifconfig for Linux) onna arren

37 ping (Packet nternet Gopher) ping is used to test connectivity by omputer name p address :\> ping onna arren

38 tracert traceroute - traces the route using MP packets :\>tracert cisco.com onna arren

39 EA isplays P/P statisitics :\>netstat t t n onna arren

40 nslookup hecks the accuracy of records :\>nslookup cisco.com onna arren

41 esting onnectivity onna arren

42 Permissions onna arren

43 ypes of Permissions Permissions allow the administrator to grant or deny access to objects (resources) on the network or the individual computer permissions hare permissions egistry permissions Active irectory permissions onna arren

44 Master ile able (M) onna arren

45 ecurity escriptors onna arren

46 indows bjects iles Process irectory Processor Printer edirector Memory hares ache ystem Logical isk hread Paging ile onna arren

47 Access ontrol Lists (AL) Each object has an AL associated with it tore access control entries (AEs) Assigned to security descriptor for file system object here are two types of ALs: iscretionary AL (AL)- Permissions ystem AL (AL) - Auditing onna arren

48 Access ontrol Entries (AEs) Grouped by resource bject type identifier Actions permitted on the object List of s of users or groups allowed to perform a specific action an be set for Allow, eny, or Audit Allow and eny AEs can exist in the same AL Audit AEs are kept in ALs eny AEs override Allow AEs Accumulated permissions for multiple AEs is most lenient unless one is deny onna arren

49 older Properties ype of object Location ize umber of files/folders older name and creation date Permissions Auditing wnership onna arren

50 wnership he initial creator of a file or folder is the owner of that file or folder older owners have ull ontrol permissions for the files and folders they create Administrators have the right to take ownership of any object onna arren

51 ile versus older Permissions Both allow you to assign special permissions as well onna arren

52 older Modify the folder permissions ake ownership of the folder elete subfolders and files contained in the folder ull ontrol Perform all actions associated with all of the other folder permissions ile Modify the file permissions ake ownership of the file Perform all actions associated with all of the other file permissions i onna arren

53 older elete the folder Perform all actions associated with the rite and the ead & Execute permissions i Modify ile Modify the file elete the file Perform all actions associated with the rite and the ead & Execute permissions onna arren

54 older avigate through restricted folders to reach other files and folders Perform all actions associated with the ead and List older ontents permissions ead & Execute ile Perform all actions associated with the ead permission un applications onna arren

55 older View the names of the files and subfolders contained in the folder. List older ile ot applicable onna arren

56 older ee the files and subfolders contained in the folder. View the ownership, permissions, and attributes of the folder. ead ile ead the contents of the file. View the ownership, permissions, and attributes of the file. onna arren

57 older reate new files and subfolders inside the folder Modify the folder attributes View the ownership and permissions of the folder rite ile verwrite the file Modify the file attributes View the ownership and permissions of the file onna arren

58 pecial Permissions onna arren

59 ile Versus irectory Permissions ile permissions override directory permissions Example Bob has no permissions on a directory but has read permissions on a file in the directory Bob can access the file but must type the full path name to do so onna arren

60 Permissions ile elete hild f a user has full control on a directory, he can delete top level files even if no delete file permissions exist hen access is granted to a file a handle is put into the object itself and the Access ontrol List is no longer checked onna arren

61 Permission nheritance ubfolders and files inherit permissions from their parent folder nheritance can be blocked Uncheck the nclude inheritable permissions from this object s parent heck box Blocking required for new permissions onna arren

62 opying versus Moving onna arren

63 Effective Permissions he combination of Allow permissions and eny permissions for each security principal: Allow permissions are cumulative. eny permissions override Allow permissions. Explicit permissions take precedence over inherited permissions. onna arren

64 esource wnership Every file and folder on an drive has an owner he owner always has the ability to modify the permissions, even if current permissions settings deny them access he owner is the person who created the file or folder thers with the ake wnership permission can become the owner onna arren

65 haring etwork esources onna arren

66 older haring n folders can be shared over the network Any folder sharing Public folder sharing Homegroup sharing onna arren

67 hared olders Permission EA hange ull ontrol Permissions Apply to folders only (not files) o not restrict local access to resources nly permission available for A efault permission is Everyone/ead. onna arren

68 onnecting to hared olders haring My etwork Places Mapped drives (indows Explorer) Mapped drives (E UE) un dialog box use U PAH \\servername\sharename\subfolder top haring omputer Management - hoose top haring from shortcut menu indows Explorer - elect o ot hare his older E HAE E HAE <sharename> /ELEE onna arren

69 haring with Homegroups Uses the Home network location to share the contents of libraries among all users Automatically configured hares libraries i in the users profiles an add libraries onna arren

70 haring the Public older implest way to give clients file sharing capability (small business networking) etwork iscovery and Public older haring must be turned on opy files to be shared to the Public folder onna arren

71 Any older haring ull control over what material on the computer is shared hich users have access and to what degree they have access onna arren

72 Managing g hare Permissions hare permissions i are independent from other permissions. ith Password Protected haring enabled, users must have user accounts on the computer or in a domain. onna arren

73 Example Jim GUP HAE ales EA EA Everyone HAGE A Managers ULL L HAGE onna arren

74 Example - Mary GUP HAE ales EY EA Managers ULL L HAGE onna arren

75 Example - om GUP HAE ales EA HAGE Marketing HAGE EA Managers ULL L A onna arren

76 Printers onna arren

77 indows Print Architecture onna arren

78 indows Printing lexibility tand-alone alone local printing Printer shared on the network Print device connected directly to LA reate a printer pool (one print server with more than one print device) onnect multiple printer servers to a single print device onna arren

79 onfiguring Printer ecurity hen password protected sharing is turned on, users must logontothe on the computer with a user account that has a password Users must have the appropriate permissions to access the printer onna arren

80 Print allows onnect Print Pause esume estart t Printer Permissions Manage Printers ancel all documents hare hange properties elete the printer hange permissions cancel and delete Manage documents your own documents Manipulate all documents ontrol job settings for all documents onna arren

81 ummary he networking stack used on indows computers corresponds roughly to the seven-layer reference model upport for both the Pv4 and Pv6 protocols etwork iscovery simplifies the task of firewall configuration he etwork Map utility uses the Link Layer iscovery Protocol (LL) to detect network devices and connections onna arren

82 ummary upports both HP manual configuration ncludes the most commonly used command line P/P tools he printing i architecture in indows is modular, consisting of the print device, a printer, a print server, and a printer driver A local printer is one that supports a print device directly attached to the computer A network printer connects to a shared printer hosted by another computer onna arren

83 ummary permissions work only on volumes ecurity descriptors are stored in the $ecure file ALs list AEs assigned to an object AEs map users or groups to permissions Permissions i are inherited it by default Effective permissions are the sum of AEs wnership cannot be given eny AEs override all other AE types for a particular permission Avoid the eny AE to limit complexity onna arren

84 ummary hare folders to allow remote usage hare permissions apply only to folders efault share permission is Everyone - ead eplace default share permissions to reduce security exposure Administrators and Power Users can share folders and share permissions i can be combined onna arren

85 Lab 4 onfigure P/P reate shares using the properties box reate shares at the command line reate share using the shares wizard onfigure both hare and permissions reate a network printer using a P port reate a shared printer onna arren