Mechanics of User Identification and Authentication: Fundamentals of Identity Management

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Even if the user tries to authenticate using an UPN, this will not bepossible Figure 3. A user sitting in front of a computer who is a member of the imme-dient. From the tickets it is clear thatthe user has authenticated successfully using the Kerberos Protocol. Because NTLM authentication does not supporttransitive trust relationships, this is bound to fail. However, both Kerberos and NTLM authentication will work from thedirectly connected forest root domain ins.

However, a solution wherein every user and computer from. The security of such an openand transparent authentication approach will depend on each and everyclient computer in both forests setting the correct permissions on resourcesto allow or deny access to computers in the other forest, which may bea huge challenge — if not impossible — for large organizations.

CISSP - Identity and Access Management Tutorial

If administrators choose to use selective authentication for a trust inthe particular direction, then an administrator of the trusting resource domain or forest will need to explicitly grant permissions to the users orgroups from the trusted account domain using the Active Directory Usersand Computers console. The Domain Admins group from the exter-nalorg. Administrators from the ins. By default, if selective authentication is enabled, users fromthe remote domain externalorg. It is interesting to see how the user access token for external userschanges, depending on whether domain wide or selective authenticationis used for the trust relationship.

Assuming that domain ins. Clients will try to use SSPI signing. The client generates an NTLM v. The clients generate NTLM v. Clients generate NTLM v. Domain controllers only consider NTLM v. The LM response is calculated based on the server challenge SC inthe following way: 1. The client calculates the LM hash from the plaintext user password.

Identity Management 101: Unwrapping Identity Management

The resulting LM hash is 16 bytes in size. The response is sent to the server. The server calculates the response in the same way as the client and compares the results. If they match, authentication is success- ful. If they do not match, authentication fails. Although the encryption algorithm may seem somewhat complex, theLM authentication protocol has some weaknesses and limitations.

First, it is based on the LM hash, which is inherently weak see Chapter3 for more details. In addition, the LM authentication protocol is suscep-tible to man-in-the-middle attacks, used by some implementations as anauthentication approach see Chapter 4. Basically, an attacker cansit in between the client and the server and relay messages between them. An attacker sitting between the client and the server can intercept theauthentication and then utilize the authenticated session. In addition tothat, as both the server challenge and the client reply are sent over thenetwork, someone with access to the communication channel betweenthe client and the server can obtain the challenge and the response, andit is relatively easy obtain the encryption key, which happens to be basedon the LM hash; an attack on the LM hash can then provide the userpassword.

The inherent weakness of the LM hash makessuch attacks feasible, and there are many tools on the Internet that utilizethese weaknesses. As a result, LM authenticationshould, in general, be avoided. It was. The NTLM v. The result is a byte hash. The NT hash is padded with nulls to 21 bytes — padded NT hash. NTLM authentication, although generally stronger than LM authentica-tion, suffers from similar problems. Man-in-the-middle attacks are feasible,and an attacker with access to the communication channel between theclient and the server can both intercept the authentication messages andthen try to reverse-engineer the encryption key, or hijack the authenticatedsession.

The server challenge and the response are sent in cleartext overthe network that makes attacks trying to obtain the password hash feasible. Because the MD4 hash, used by the NT hash calculation, is stronger thanthe LM hash, the password is not so easily exposed. However, there arenumerous attacks on the MD4 algorithm that might be able to computeeither the original password or a colliding password a different passwordthat would generate the same hash.

As a result,the NTLM authentication mechanisms should still be avoided if possible. It was meant to provide a stronger authentication mechanism for www. NTLM v. The uppercase Unicode username and the uppercase Unicode target user database this is typically the domain name, or can be the server name in the case of local accounts on the server are concatenated to form the target string TS.

The result is the byte NTLM v. The second part of the NTLM v. As the client response is based on the. On the other hand, becausethe BLOB is included in cleartext in client responses, and therefore canbe considered known to the attacker, it can be computationally feasibleto obtain the NTLM v. Unlike LM v. However, if the attacker does not need theplaintext password, he can use the NTLM v. From an NTLM v. As with most other authentication mechanisms, Microsoft doesnot provide information for the authentication protocol mechanics. In thecase of NTLM2 Session Response, Microsoft does not even mention itanywhere, so the name for this mechanism was given by Internet securityresearchers see [48].

The client generates a random 8-byte challenge — CC. The client challenge CC is padded to 24 bytes using nulls. The client concatenates the server challenge SC with the client challenge CC — resulting in the challenge string. The challenge string is hashed using the MD5 algorithm. Using the plaintext user password, the client calculates the NT hash using the MD4 hash on the user Unicode plain password. The result is the NT hash.

Although some attacks have been reported as capable of reducing thecomplexity of the encryption, the NTLM2 session response protocol is stillconsidered reasonably secure. As with most challenge-response protocols,dictionary attacks may be effective and brute force attacks may be effectivein the long term. It is primarily used for compatibility reasons. The client concatenates the uppercase username and the uppercase authentication database name servername or domain name and calculates the HMAC-MD5 for the resultant string using the NT hash as the key.

The result is the NTLM v. The client creates a random challenge of 8 bytes — the client challenge CC. The server challenge SC is concatenated with the client challenge CC. The result is the challenge string. The byte result is the CRLA value. This subsection demonstrates some of the mostcommon NTLM authentication scenarios. Interactive Logon: Windows NT 4. Interactive logon process: 1. To protect from replay attacks, the client obtains the current time from the local computer clock and sums it with the client response to the server challenge.

The domain member submits the plaintext username, the encrypted time stamp, the plaintext time stamp, and the encrypted password hashes utilizing the existing secure channel and passes the authen- tication request to the domain controller using the NetrLogonSam www.

It is important to note that although the client uses the current time stamp in the calculation, this value is then sent to the server, and the Secure Channel authentication protocol does not rely on synchronized clocks on the client and the server. The NetrLogonSamLogon RPC interface on the domain con- troller calculates the time stamp received in the client logon request using the same algorithm as the client and ensures that the packet has not been replayed.

It then performs another time stamp encryption using the client-provided time stamp, increased by one. If the LM and NT hash values match, the user is authenticated and the domain controller returns an access token structure to the user; see phase C in Figure 4. The server includes the encrypted sum of the client time stamp with the client response, increased by one, as calculated in Step 9. If the secure channel is not encrypted sealed or signed, information is returned in plaintext.

The domain member receives either failure status or the access token of the user as a result. The client authenticates the time stamp provided by the server and ensures that the server reply is genuine the server has managed to decrypt the time stamp from the client, increase it by one, and then encrypt it again and has not been replayed. An access token is created from the user token, and a user shell is created. The access token is used by the user shell to access resources. It is important to note that the secure channel utilizes the machineaccount password along with other random parameters to generate asession key for data protection.

The NetrLogonSamLogon functiontransfers encrypted user credentials over the network but still utilizes thesecure channel between the client and server that, in addition to authen-ticating the communicating parties, may provide for additional channelsigning and encryption sealing. The above interactive authenticationsequence is only valid for Windows NT 4. If the client and the server support Kerberosauthentication, they will use Kerberos instead. The secure channel is anNTLM technology. Logon process: 1. The user sitting in front of a computer in Domain B submits a username and a password, as well as its own domain name, Domain A; see phase A in Figure 4.

The client computer sends the request across its secure channel to a domain controller in the same way as it would do for an authentication request in its own domain; see phase B in Figure 4. The domain controller of Domain B decrypts the RC4 encrypted password hashes using its session key with the domain member in the same way as it would do for an authentication request in its own domain. Because the domain controller of Domain B does not have infor- mation about usernames and password hashes in Domain A, the.

Namely, it behaves like a domain member of Domain A logging into the domain and utilizes the interdomain secure channel that it has to a domain controller in Domain A to encrypt the password hashes using the interdomain secure channel session key as the key, and then passes them using the NetrLogonSam Logon RPC or one of its derivatives across the secure channel to the domain controller in Domain A as if it were a workstation in Domain A; see phase C in Figure 4.

The domain controller of Domain A receives the request and handles it the same way as it would handle a request from a domain member in its own domain. It then uses the secure channel to pass a user token or an authentication failure reply back to the Domain B domain controller; see phase D in Figure 4. The Domain B domain controller receives the authentication request from Domain A domain controllers. It then passes the user token or authentication failure message back to the workstation attempting logon; see phase E in Figure 4.

The user access token on the client workstation is created based on the user token from the server, and an initial shell is created for the user; see phase F in Figure 4. Network Logon: Windows NT 4. Network logon process: 1. A user who has already been authenticated interactively on the client computer utilizes a client application that requests interaction with the server; see phase A in Figure 4. The server submits the LM and NTLM challenges that it generated and sent to the client, as well as the client responses to both challenges; see phase C in Figure 4.

Using the server-provided challenges, the domain controller calcu- lates the LM response and the NTLM response using the hash values in its own account database for the user trying to authen- ticate. The domain controller compares the responses it calculated with the responses provided by the client. If the responses match, the client has been authenticated successfully. If the responses differ, the authentication has failed. In any case, the authenticating domain controller replies to the NetrLogonSamLogon request across the secure channel back to the requesting server.

The reply contains. The server receives the user access token encapsulated within the NetrLogonSamLogon reply. If the authentication was success- ful, it uses the user token, provided by the domain controller to build an access token for the user, and then impersonates the user. The server returns a success or failure result to the client as the last phase of the NTLM authentication process; see phase E in Figure 4. The server utilizes the secure channel to its own domain controller by invoking the NetrLogonSamLogon RPC function across the secure channel to the Domain B domain controller and providing the LM and NTLM challenges that it generated and sent to the client, as well as the client responses to both challenges; see phase C in Figure 4.

The domain controller for Domain B cannot authenticate the user, so it needs to perform pass-through authentication to domain controllers of Domain A. Using the server-provided challenges, the domain controller for Domain A calculates the LM response and the NTLM response using the hash values in its own account database for the user trying to authenticate. The domain controller for Domain A compares the responses it calculated with the responses provided by the client. In any case, the authenticating domain controller replies to the NetrLogonSam Logon request across the secure channel back to the Domain B domain controller see Frame 44 in Figure 4.

The reply contains a user token, which is the same as if the client was authenticating interactively; see phase E in Figure 4. The domain controller for Domain B receives the reply and decrypts it using the session key for its secure channel to the Domain A domain controller. It then forwards the reply across its secure channel to the server; see phase F in Figure 4. If the authentication was success- ful, it uses the user token provided by the domain controller to build an access token for the user, and then impersonates the user. The server returns a success or failure result to the client as the last phase of the NTLM authentication process; see phase G in Figure 4.

It providesbrief background information and then presents the naming concepts, themodel of trust, the data structures, and the protocol mechanics. TheKerberos Protocol was the authentication system for the Athena project. Kerberosversion 4 was released to the public and immediately became popular. Other differencesinclude the format of principal names, key salt, the use of forwardableand proxiable tickets, and transitive cross-realm authentication. Virtuallyall Kerberos implementations in use today are based on Kerberos version 5.

Hello phase 2. Server Authentication phase 3. Client Authentication phase 4. The Client Hello and the Server Hello messages are usedto exchange information between the client and the server at this stage Table 4. Table 4. The serverreplies with a Hello message that has a similar structure. The server Hellomessage provides a unique session ID and selects the cipher suite andcompression algorithm from those suggested by the client.

Apparently,the server will choose a cipher suite and a compression algorithm thatare supported and preferred by the server. A server that has an X. If the server does not possess an X. Does it have a valid signature, and is it within its validity period? The client typically replieswith a Client Key Exchange message where it generates a pre-mastersecret between 48 and bits in size, encrypts it using the encryptionprotocol chosen by the server at the Hello Phase, and the server publickey or temporary public key received during the server authenticationphase as the key.

This message is used as proof that the client possesses theprivate key for the public key it has provided. The server will check theclient signature using the provided public key. The PRF function is used for key expansion. If the number of characters is odd, each containsthe middle character as well. A set of keys isgenerated from the master key that is used by the client and the server.

For algorithms subject to export regulations, see below. Keys used by algorithms that are subject to U. All further messages from the clientwill be protected. The server replies with the same two messages and allthe communication continues using the negotiated protection mechanismsand keys. The Change Cipher Spec message is only an indication to startusing the newly negotiated parameters.

The Finished message contains acryptographic hash of the negotiated parameters. If later on the client wants to establish a session to the same serverusing the same parameters, the client can send a Hello message usingthe previously obtained session ID. If the server still has the session IDin its cache and is willing to resume the session, it replies with a Hellomessage that includes the same session ID.

Both the client and the serverthen send a Change Cipher Spec message and immediately switch toprotected communication. A typical SSL handshake that involves client authentication is shownin Figure 4. The client generates a pre-master secret and encrypts it.

The client sends Change Cipher Spec and Finished messages. These indicate effective protection of the channel see Frame 6 in Figure 4. The server replies with Change Cipher Spec and Finished messages. The client authenticates the server by generatingthe premaster secret and encrypting it with the server public key so thatonly the server can decrypt it with its private key. In this case, the client provides a hash of allthe messages between the client and the server up to the last one, andgenerates a keyed hash of these messages using a hashing algorithm suchas MD5 or SHA-1 and the master key as the key.

This proves that theclient has provided a public key and has a corresponding public key. Once the server knows that the client owns a private key for a publickey provided by the client as well , the server can now perform a lookupusing this public key against a directory to determine the identity of theuser. Once the identity has been determined, the server can identify orimpersonate the client see Figure 4.

A typical SSL handshake thatinvolves client authentication is shown in Figure 4. These indicate effective protection of the channel see Frame 10 in Figure 4. As discussed, once the client has been authenticated, the server canidentify or impersonate the client. In this case, the server performs a lookup for the client public key against Active Directory.

If a user object with a matching public key attribute is found in Active Directory, the server impersonates the user. The model of trust here is the following: if the client has provided a public key and has proved to have a corresponding private key, and if then an administrator has published mapped the public key in Active Directory, Schannel can then impersonate the user.

An administrator can provide mapping between users and public keys for the local service such as IIS. The administrator can provide a list of public keys and the associated user for each public key; the password for the user must be provided as well. Once the correct mapping is found, the server will impersonate the user using the provided username and plaintext password. The difference between one-to-one and many-to-one mappings is that the former uses a separate public.

IIS uses the provided username and password and performs a password logon locally to impersonate the user. This is essentially an authentication protocol transition technology, wherein although the client does not use Kerberos authentication to access the server, the Kerberos tickets are eventually issued to the server. Therefore, S4U may need to be used with constrained delegation settings see subsection 4. Schannel can then imper- sonate the user. In the very beginning, Telnet was just a simple way to connect toa host over the network. Technicallyspeaking, the Telnet application provides a terminal emulation environ-ment where the administrators and users connect to the host or deviceover the network instead of a serial link.

However, the Telnet Protocol and application suffer from serious securityweaknesses. User authentication using conventional Telnet access is per-formed using a standard Login dialogue, wherein the server prompts theuser for a username and password, and the user provides both in plaintext. The entire communication over the network is a stream of characters ineach direction, which can easily be captured, interfered with, etc. Fur-thermore, in the early Telnet implementations, the entire Telnet sessionwas neither encrypted nor was its integrity being authenticated. Later on, the Telnet Protocol went through a number of functionalchanges, and Telnet options were added to the protocol that allow theclient and the server to negotiate their behavior in various aspects usingin-band special characters that, unlike other characters, are not displayedon the client screen.

Furthermore, under some circumstances,the authentication option allows the client and the server to perform clientauthentication transparently for the user, without going through the logindialogue and requesting the user to type in his username and password. This mechanism is supported by virtually all Telnet serversand clients. Telnet login authentication works as follows — see Figure 4.

Upon successful TCP session establishment and potentially exchange of Telnet options , the server sends a plaintext string prompting the user for a username see Frame 23 in Figure 4. The user types in his username on the Telnet client computer.

Mechanics of User Identification and Authentication

The client computer would typically set the TCP PUSH option for packets from the client to the server so that a small number of characters very often just one — the key that the user has just pressed are sent to the server immediately. Thus, the username is typically contained in a series of frames, character by character; see Frames 29, 32, 34, 37, and 43 in Figure 4.

The server then replies with a prompt for the user to provide a password; see Frame 43 in Figure 4. The client types in the password. The server authenticates the user using his plain username and plain password. Typically, at this stage the server forks a new process or creates a newthread and impersonates the client. It then typically sets up the userenvironment and provides the user with a command prompt. Technically speaking, with Telnet, every character typed locally fromthe client is sent across to the server whether it will be just one bufferingor many depends on the use of the Nagle algorithm that can potentiallybuffer remote operations and then remote characters are sent back tothe client.

The sending of the characters can be buffered, or one by oneas the user presses the key. Anyone with access to the network in betweencan collect all the characters from the authentication process and obtainthe plaintext username and password. In general, this authenticationmethod is insecure and is strongly advised against. The Telnet authenticationoption is only a generic mechanism for authentication negotiation.

The www. In addition, the client andserver can select to encrypt or provide data integrity for user data withinthe Telnet session using a session key based on user authentication. The Telnet authentication option is not widely supported by Telnetclients and servers. The most popular implementation is the Telnet clientand server distributed with the MIT Kerberos suite.

The authenticationmethods supported by this suite are Kerberos v. As part of the Telnet Authentication Dialogue, the client and the servernegotiate an authentication mechanism. The Telnet client and server may decide to negotiate additional sessionparameters. The usersession that produced Figure 4. Connected to dennis. COM service principalname that is used by the Telnet service on host dennis. There-fore, the client can use the ticket to authenticate to the server using theTelnet Authentication option and providing its Kerberos ticket for dennis.

Toallow for a mapping between the Kerberos ticket and a local user on theserver computer dennis. The user is not provided with the legacy Telnet logindialogue. Instead, the server accepts the Kerberos credentials and mapsthe Kerberos principal with user principal name Susan INS. COM to the www. The Telnet Authentication Option process is as follows see Figure4. The client connects to the server using the Telnet Protocol. The client provides the server with a list of options that it wants to negotiate.

Among them is the Telnet Authentication option 0x25 see Frame 4 in Figure 4. The client selects an authentication method using the Telnet Authentication IS command, and submits its selection along with client authentication information appropriate for the selected authentication method see Frame 8 in Figure 4.

The server follows the authentication mechanism and checks the client response. It then generates a response to the client. If the client requested server or mutual authentication, it follows the authentication protocol mechanism to authenticate the server reply using the Telnet Authentication Option IS command. Hence, user authenticationfor FTP is different from Telnet authentication.

Name dennis. Password: password User DaVinci logged in. Remote system type is UNIX. Using binary mode to transfer files. FTP simple authentication is apparently insecure. Thus, FTP simple authentication should be avoided if possible. The idea isthat if FTP Simple authentication is widely supported but weak, we shouldnot force users to use their real usernames and passwords and thus exposethem in cleartext across the network. Instead, anonymous FTP serversimplement the special anonymous users anonymous and ftp that arenot used to impersonate the user with own security privileges but withgeneric, one-for-all privileges.

These credentials are used for loggingpurposes only and not to impersonate the user. The anonymous FTP authentication approach is appropriate when FTPsites provide public resources, which is the case for many resources onthe Internet. However, if the FTP server is to provide resources that requirerestricted access, then anonymous authentication is not appropriate andother FTP authentication methods should be considered.


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The verbs use parametersthat are Base64 encoded. Once the client and server have negotiated the authentication mech-anism that they will use, they use the ADAT verb to send authenticationmessages in both directions, and messages are Base64 encoded. Upon successful authentication, the client and the server can start toprotect both the control channel and the data channel. RFC onlydiscusses the negotiation mechanism for security protection, and not theactual encryption and data authentication mechanisms — these are pro-vided by the negotiated security mechanism. This means thatthe server and client need to successfully complete the authenticationprocess, start protecting control messages, and only then are they able todowngrade to a cleartext channel.

This is an important considerationbecause it protects against attacks where an attacker might inject CCCcommands into the control channel that can downgrade the protectionlevel. Data channel protection is negotiated separately from the controlchannel. The client and server needto negotiate protected message size using the PBSZ verb. Encryption without data integrity authentication is not supported byGSS-API, so this is not a valid choice for protecting the control or datachannel when GSS-API is selected as the authentication mechanism butmay be supported by other security mechanisms.

The client connects to the server control channel and receives the server banner see Frame 4 in Figure 4. Currently, GSS-API key exchange is only supported by a limited numberof SSH implementations, but the growing number of Kerberos-basedinfrastructure solutions is likely to make it more popular in the future. The main idea of RPC is to allow for remote execution of codeacross the network. A client can prepare a set of parameters that can thenbe provided as procedure arguments at the client computer.

The server application then executes the requested procedureusing the provided parameters, and then returns the result to the clientacross the network. Among the www. The RPC Protocol provides for mutual authentication. Itscontent depends on the authentication mechanism being used.

The following subsections discuss the RPC authentication mechanisms. In that case, the client and server can use RPC Null authen-tication.

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The client will be anonymous to the server, and the client. The server will typically start a newthread or process for the client, and will do so using a generic accountfor Null anonymous access — typically one with very limited privileges. A typical example of an application that provides public informationis the RPC portmapper. It is used by clients to enumerate the RPC serviceson a server, and does not per se provide access to the actual applications.

For example, a user on computer linus can use the rpcinfo tool toenumerate RPC services on server dennis. Null authentication is performed as follows see Figure 4. It is common for the RPC port to be dynamically negotiated via the portmapper mechanism. The remainder of the packet contains the actual RPC request. In the case of impersonation, the RPC server applicationwill typically launch a new thread or process with the privileges of theauthenticated user.

The client submits this informationusing the plaintext structure shown in Table 4. To ensure that all user and group IDs are aligned, the RPCserver and all its clients need to use a standard numbering scheme foruser and group IDs. The approach to accomplish this can be manual or,alternatively, automatic. User and group information synchronization can. However, both the hostnames and the IP www.

Hence, theserver cannot validate that the request is genuine and coming from atrusted source. The most widespread although not necessarily the best approach istunneling RPC within SSH, which can provide for both communicatingparty authentication client and server and user authentication, as wellas channel encryption and integrity authentication. The symbolic name used by a user to authenticateto the RPC server is called the netname.

RFC provides a variation and suggests that the username consist ofthe name of the server or the operating system, followed by the user IDon that server — for example, unix. In order to use the private key, theclient needs to decrypt it. Provided that the conventional user passwordis the same as the password used to encrypt the private key, this willhappen automatically. The keyserver daemon runs on the client computerand securely caches the decrypted user private key.

Both the client and the server use encrypted time stamps in the www.

Mechanics of User Identification and Authentication - CERN Document Server

The keyserver on the client computer generates a random 8-byte conversation key. The keyserver uses the public key directory to look up the server public key. To use it as little as possible, the master common key is not used to encrypt time stamps. The client prepares the plaintext authentication structure depicted in Table 4. The plaintext structure in Table 4. The server then returns to the client the internal index nickname. Using this key, and its own public and private key, the server generates a master common key and uses it to decrypt the conversation key from the Full Network Name structure;.

To protect from replay attacks, the server will drop requests that seem to have been generated before other requests already received from the client. It is important to note that the server uses the time stamp sent by the client, rather than checking its local time — the server authenticates its identity to the client by proving that it knows the conversation key, and that it can successfully decrypt, manipulate, and encrypt the client-provided time stamp. Once the server has decrypted the client full name from the initial request, the server decreases both the client time stamp and client time stamp — one by one, and then encrypts them using DES CBC with the conversation key see Table 4.

When the client receives the reply from the server, the former is able to authenticate the server, as no other user or computer can know that secret conversation key, calculated independently by the server and the client. The client still uses the current time to generate time stamps, which then get encrypted using DES and the conversation key as the key see Table 4.

The use oftime stamps provides for effective protection against replay attacks, andthe use of public key cryptography mitigates the risks of man-in-the-middleattacks, while at the same time providing a reliable mechanism for keymanagement using public key-based master keys. Unfortunately, the DESencryption algorithm is now considered weak. The Kerberos v. Because Kerberosv. The server submits the following structure to the client see Table 4. The client and server may need to exchange a couple of tokens, depending on the authentication mechanism being used.

Subsequent messages between the client and the server can be protected with GSS-API integrity and privacy, depending on the quality of protection QoP chosen. It is currentlyconsidered a secure way to authenticate users and transfer data. As the Sun RPC interprocess communication mechanism possessesits own methods for authenticating network users, the NFS Protocol itselfdoes not need to provide for user authentication, and uses the readilyavailable Sun RPC model.

More information regarding Sun RPC authenti-cation is available in section 4. Alternatively, the client can directly connect bind to an RPC application by specifying its unique ID. The rest of the RPC session uses the dynamic port. For more information, see subsection 4. Microsoft SQL Server provides for two different authentication methods: 1. Dobromir Todorov. Do you have any questions about this product? Ask a Question. Pricing History. Questions 0. I would like to report this offer Please select a reason for reporting this offer.

Is your question one of these? How much will it cost? How do I pay? Can delivery be arranged? How long will it take and how much will it cost? Where can I purchase, which shops? Do you have stock? Can you quote me? May I buy in bulk and do you offer discounts for bulk buying?

Amazon Price History

How to purchase For a product displaying a "Add to Cart" button the product can be purchased directly on PriceCheck's Marketplace. For a product displaying a "View Offer" button clicking the button will direct you to the product on the associated shop's online store where you may complete the purchase.

Cost The price displayed for the product on PriceCheck is sourced directly from the merchant. The price of the product can be seen on PriceCheck. How to pay Our listed shops offer various methods of payments which are displayed on their websites. We only partner with reputable online stores, so think trust, think reliability and think the best possible prices.

Delivery For a product displaying a "Add to Cart" button the product can be purchased directly on PriceCheck's Marketplace. We are pleased to offer our customers door-to-door delivery by courier anywhere in South Africa. The delivery time is a combination of the merchants processing time and the days allocated to the courier. The processing time is set by the merchant and can be 1,3,5,7 and newly added 14 or 21 days. For a product displaying a "View Offer" button clicking the button will direct you to the product on the associated shop's online store. Yes, delivery can be arranged as shops offer various delivery methods.

All of our shops use the South African Post Office or reputable couriers to deliver goods. Unfortunately, PriceCheck can not clarify how long delivery will take, or how much delivery costs. However, some shops do display an estimated delivery time and cost on their site. So if the merchant has a processing time of 3 days, we add 5 days to that for the courier and display it as days for delivery. We do not source products. Our platform features offers from merchants who have signed up with PriceCheck.

You are welcome to search for the product on our website and make contact with any of the merchants featured on PriceCheck for more information regarding their offers. All merchants contact details can be found at pricecheck. Stock PriceCheck is a discovery and comparison platform.

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