Category: Literature Review on Projects

By making use of the different types of the storage resources in an efficient manner the storage consolidation is capable of offering the considerable savings of cost towards the traditional DAS. The major cost within the establishments of the DAS is that there is a necessity of managing the different systems in which the original storage is considered to be the primary cost within the NAS as well as SANs. The total number of the individuals who are needed to help the DAS entirely depends on the total numbers of the servers that are installed. Anyhow the servers are not being added by means of the SANs and the NAS they will just perform the storage process and for this reason there is only a necessity of the less number of users.

If the customers imagines the total numbers of the TB that belongs to the data could be easily controlled by means of the administrator run which is full time starts from 1.5 to 5.0 for the purpose of the DAS through the 6.0 to 13.3 for the purpose of NAS or SAN. On the other hand if the customer specifies that the usage of the disk is nearly 50% upon the DAS then that specific usage will increase nearly to the 90% which is intended for the purpose of the SAN as well as NAS. The SAN as well as NAs are capable of using the capacity that is available in an efficient manner and it is even simple to scale up the NAS and the SAN. 

Fig: Breakdown of the storage costs per MB for the DAS, SAN as well as NAS. 

This figure will specify the procedure of cost breakdown for the purpose of the DAS, SAN and NAS. By this figure it is clear that the administration is the majority of cost for the DAS and the storage media is the majority of cost for the SAN as well as NAS.

The high availability, the reliability as well as the performance are the major reasons for the establishing the storage consolidation. The high availability is being used for the purpose of accessing the data without any interruption. The reliability is intended for the purpose of the decreasing the downtime and to improve the continuity of the business. The performance is meant for the purpose of processing the quick transaction in order to develop the entire productivity.

Each and every specified attributes could be easily accessed by making use of the SANs as well as NAS. There is a necessity of the several types of the equal systems in which one system will have no work to do that will even wait for the failure of the other system in order to perform this action. Within the entire process if the server of the DAS gets failed then the entire data storage which is associated with the server will not be available and the data can be restored when the server is restored. The process of decreasing the performance as well as the availability for allowing the data to be more vulnerable to the disturbances is the time consuming process and cannot be processed in an easy way. The final solution for the user to access without any interruptions is using the SAN or else the NAS which is not having any failures as well as using several numbers of the paths that are related to the data access times. The final conclusion is that it is better to use the SAN or NAS than that of the DAS.

Because of the presence of more numbers of the smart switches the SANs as well as the NAS are capable of scaling up and out which could be surrounded by the unnecessary failure fabrics. By making use of the different types of the path these fabrics are capable of detecting the different failures as well as it will even redirect various requests of the users towards the mirror images.

By performing this process the availability of the user will not be disturbed and the servers as well as the storages will be added and then there is a necessity of the programmed downtime which is capable of decreasing the productivity of the user. The DAS is being connected with one or more number of the servers and if it uses the other server then it will not be able to access the capability of the server which is already used in the process.

The different types of the data of the users are being transferred by the SANs as well as NAs towards the available capacity. The storage which is unused can be allotted to the different servers by making use of the strategy called storage pooling. In order to attain the scalability of the performance the process of carrying out the storage consolidation is considered to be one of the best method.

The File or Web and Database Applications

The main concern within the process designing the storage consolidation is the access towards the different types of the applications. Each and every application will have its own methods and approaches for performing the process of data transfer. The major difference among the SAN and the NAS is the data transfer mechanisms through which the data is transferred by using some applications.

The SAN will move the huge chunks of data that is being transferred in a reliable manner by making use of the fabric protocol which depends on the different commands of the SCSI. But the NAS totally depends on the TCP or else the IP Ethernet which is capable of transmitting the small chunks of data. In different types of the circumstances the SANs are utilized as the subsystem of backend storage for the purpose of the installation of the large NAS in order to make the restore and backup tasks easy which will even decrease the traffic present within the networks of corporate.

The specific types of applications like the database and emails which utilizes the block access process in order to achieve the I/O on the data are considered to be the best applications that are more suitable to the SAN. The different applications could be easily balanced within each and every server towards any types of the storage fabrics.

By offering the on demand capability the storage is being distributed towards the different types of the servers. By decreasing the development and growth prices the reliable performance delivers the high bandwidth, the low latency interconnects as well as the switches of fibre channels. In the present circumstances related to the business there is always a necessity of the storing the consolidation applications in a success manner to improve the performance of the continuity systems of the business.

The file is considered as the set of the collection of the information which is rationally assembled into the group of single individual which is being referenced through the specific single name called filename. Basically there are two types of the end user devices such as data files such as the text documents, the spreadsheets, the images, videos and the system files like operating system, the binaries as well as the libraries of the applications.

The files are explained with their name as well as they are being stored managed and then accessed. The directories are so called the folders that can be considered as the organizational structures which are being utilized by the file systems towards the group files. The main purpose of the file systems is to secure and store the different types of the files, the system and data files, the metadata which is upon the storage media.

The lasting data is even maintained by the storage media which is considered as the data that is gathered from the deleted files. By making use of the end user devices as well as the forensic analysis process the lasting data could be recovered in an easy manner.

Solid state memories

Memories of the solid state are becoming rapidly the medium which is dominant for storage of information in digital systems. Steady is presented in their ascendance, slow is presented until recently. Dramatically solution has modified during previous few years as a consequence of circuit and technology advances providing substantial advantages to the user in words of versatility, performance and cost.

The industry of semiconductor is considered as one high technology which is characterized by ever greater complexity, improved performance and decreasing prices. With this supply frustrations, product obsolescence and poor component standardization, with product life which value is less than five years time. In no place has this true than in memories of semiconductor as well as especially integrated circuits of random-access-memory of metaloxide-silicon dynamic. 

The task of memory-systems designer has turn into very many anxieties not only with choosing the most suitable component for specific application, however also in selecting the best technology as well as the correct vendor.

RAM

Memories of the computer can be separated into important categories: serial-access as well as random-access memories, a crack which reflects performance/ cost trade-off by the manufacturer of the computer. R.A.M. presently specifies the market major part. It was improved with a strategy of product targeted at emulating systems of core memory. With this market which is associated is considered as largest technologies range, manufacturers and devices. Even within any one device and technology capacity, different products proliferation may shown. Such as, the dynamic RAM of 4 k ^-channel available having at least five of three different packages pin out versions with numerous variations of electrical-specification. Recently only did the types of the 16-pin 4027 really undisputed leadership of the command. 

Second category is also specified here which is named as serial memories. These memories are specified in which information may be located in or subtracted from a place in specific sequence of the time. The shift register of serial-out/ serial-in is considered as simple example. At current time serial memory is adapted using magnetic disc or tape. Now this position is threatened by two technologies which are new. These are magnetic-bubble devices and charge-coupled devices. In specifically require to compare and consider the roles of m.b.d.s. and c.c.d.s in micro computing systems as serial memories.

Charge coupling is considered as all mobile collective transfer within the element of a semiconductor mobile electric charge saved to similar, by voltages external manipulation adjacent element. The stored charge quality in this ‘packet’ of mobile can widely vary, based on, such as, the voltage which is applied. The electric charge amount in every packet can specify the data in an analogue sense. 

Basically two c.c.d types are presented, one is buried channel and another one is surface channel. With devices of surface channel, the charge is saved as well as passed at the surface of silicon, whereas, with devices of buried-channel, the silicon substrate doping is changed so that the transfer and storage of charge takes area in the silicon bulk just beneath the surface of silicon.

In operation, the device of a charge-coupled can be about as an m.o.s. transistor simple extension, as well as is dramatically shown in figure. The basic devices have closely spaced control linear arrays of electrodes on the electric layer of continuous silicon-dioxide dielectric, which covers the substrate material of the single-crystal silicon. Charge transfer as well as storage performed in the device channel regions generally which are bounded by stop diffusions of high concentration channel. Within the beneath of the depletion region the channel is presented as given electrode is named a charge packet.

In this scenario, examine how distribution and the geometry of patterned islands, i.e. length, period and size of island affect the read channel performance in bit error terms against SNR and thus identify the configuration of the best media to provide performance of the optimum read channel. In addition, characteristics of other media, for example thickness of film as well as an SUL presence, will be inspected.

To facilitate work, simulation of a readout has been improved which considers the patterned media three-dimensional (3-D) nature and predicts accurately the waveforms which are replayed as the media characteristics functions. In addition, the readout simulation of the 3-D predicts also the contribution of the signals arising because of inter-track-interference (ITI) in waveform which is readout.

To recognize the performance of the data recovery, “partial-response maximum-likelihood (PRML)”simulation of the read channel has been also developed. The gained simulation will be employed to assess the common partial-response goals range performance applicable for make use in storage medias which are considered as patterned media.

Read channel of patterned media as well as designs which are wrote has been previously analyzed by Hughes for media which is 100-Gb/in² without and with an SUL. The work which is existed here focuses on the storage densities of 1-Tb/in² as well as in many areas enhances understanding by using the replay process 3-D model as contrasted to Ruigrok and Potter two-dimensional (2-D) approaches, which more predicts accurately the probable distribution underneath read head of the giant-magnetoresistive (GMR) in an SUL presence. 

By introducing ITI more realistic case in wave form which is replay; by examining how the island bit-aspect ratio (BAR), period, geometry, as well as distribution affects the performance of the read channel BER; by accurately modeling the lithography jitter effects consideration in the position of island both shifts and variation in the island size; by making use of simulation of the full channel, which models all the components of the read channel and creates the BER by measuring data at the read channel output in error, rather than using approaches which are considered as analytical procedures; and by examining a read channel of PRML incorporating polynomial of generalized-partial-response (GPR) which is optimized.

An Investigation of the Effects of Media Characteristics on Read Channel Performance for Patterned Media Storage:

In magnetic storage systems data capacities advances have been possible only using both continued refinement of the recording and the storage media as well as the heads replay properties. Longitudinal magnetic media is employed by present commercial systems, where the magnetization lies’ direction in the continuous magnetic film plane. It is predicted that the magnetic recording systems future generation will employ increasingly specific media, where magnetization lies direction perpendicular to the film plane; in this management, increased capacities of the storage have been examined by making comparison with the longitudinal media.

The shift to perpendicular media has created many technical challenges; notably most, the requirement for heads of the single-pole recording, media fabrication which is thin-film perpendicular on magnetic under layers (SULs) which are soft, as well as the design development of new read channel by reason of the differences of the signal spectra between perpendicular and longitudinal systems.

All challenges have been tackled successfully as well as made commercial perpendicular drives realization possible. But, beyond perpendicular media, few people consider the patterned media use will be required to gain densities of the storage media in 1 Tb/in² excess as well as trounce the physical barriers that made restrictions on densities of ultrahigh-storage in continuous media.

Such shift which is a paradigm will introduce undoubtedly further difficulties which are technical that must be beat to realize specific storage systems; not slightest, the difficulties associated with the media fabrication.

Introduction to Vulnerabilities in the Technologies of Networked Storage :

The process of implementation of the NAS as well as the SAS is not such easy and this process is considered to be one the difficult aspect. The special type of approach called the DID is being utilized in order to reduce the different types of the risks by means of separating the storage layers of the networks into two different layers which will even specify the different types of vulnerabilities in it. 

By making use of the DID approach the difficult exploitations of the NAS and SAN are being divided into four different types such as:

• The devices which are upon the storage network
• The data access
• The network connectivity
• The management access 

The vulnerabilities that are present in the NAS and the SAN deployments are explained as follows: 

The vulnerabilities of NAS

Layer 1 the devices on storage networks

The devices which are present in these layers will contain the different types of the filers or else the servers of NAS which are capable of sharing the different file systems within the total network or system. The different vulnerabilities within this layer are surrounded by OS upon the filer or else the server which involves:

• The access which not authorized because of the presence of the mechanisms which are having delicate authentication as well as the approvals. The best example for this is the utilization of the defaulting usernames as well as the passwords which are being configured upon the applications related to the NAS along with the authentication of weak username and the password.
• The different types of the security violations which are depended on the vulnerabilities which are published within the OS as well as the different services offered by means of the OS.

The Layer 2 data access

The data which is been stored within the NAS is distributed by making use of the different types of the file systems like the CIFS –common internet file system, the SMB-server message block as well as the NFS-network file system. The actual vulnerability within this process is the unauthorized authentication which is as follows: 

• The CIFS share level authentication will utilize the single password for each and every share as well as the different passwords are being shared within the form of plain text that are more exposed to the vulnerabilities.
• The user level authentication of the CIFS which is depended on the LanMan is not secured in a proper way.
• The data loss because of the reliability as well as the presence of the different types of viruses, worms as well as the DoS –denial of service attacks

 Layer 3 Network connectivity

As the entire applications of the NAS are totally based on IP which are more exposed to the different attacks such as the Denial of Service attacks and session hijacking and the IP spoofing which are even addicted towards the vulnerabilities that are based on IP. 

 Layer 4 management access:

The device administration, file systems as well as the stored data are happened to be the applications that belong to the management of NAS. There are different types of vulnerabilities such as:

• The unauthorized access to the systems by making use of the different types of the sniffing passwords because of the utilization of the protocols of clear text communication such as the telnet as well as the HTTP protocols for the access.
• The other types of the unauthorized access because of the presence of the mechanisms of weak authentication as well as authorization and the lack of the managing the authentication factors. 

The vulnerabilities of SAN

Layer 1devices on the storage network

Even though the servers are been connected towards the SAN are capable of accessing the data which is stored on the devices of SAN there are some vulnerabilities that are as follows:

• The unauthorized access because of the presence of the weak authentication and the authorization of the schemes that belongs to the OS that are connected upon the servers.
• There are different types of security violations that are published within the OS along with its services offered based on the servers as well as the hosts. 

 Layer 2 data access

The significant data could be easily stored and secured in the SAN by making use of the different servers that are configured which are similar to that of the NAS applications. By this process the data can be easily accessed by the mail servers as well as the servers of the database. The unauthorized access because of the weakness within the CIFS shared levels along with the establishments of the user authentication levels. The data losses are happened because of the presence of the tolerant access towards the storage devices by making use of several types of hosts upon the SAM.

Layer 3 network connectivity

The different types of the devices related to the SAN are being associated by making use of the HBAs, the hubs, switches as well as the different fibre channel protocols. The SANs are happened to be more protective when they are having the network characteristics which are isolated. The unauthorized access because of the vulnerability of the fibre channel protocol. The vulnerability is because of the security violations which are not configured in a proper way and will utilize the different types of the default configurations. 

Layer 4 – management access

Reducing vulnerabilities is the process of management of the different devices which belongs to the SAN. The main vulnerability is because of unauthorized access because of using the sniffing passwords and the access protocols that are not secured. This process is because of the lack of access control as well as the different types of auditing measures.

Introduction to SAN Network Seminar Topics:

The SAN- storage area network

The SNIA- storage networking industry association specifies that the SAN is the type of network and its major task is to transmit the data among the two different types of the computers as well as the storage elements that are diagonally opposite towards the storage elements.

The storage area network is made up of the communication architecture that offers the different types of the material associations as well as the management layers that will arrange the connections of the storage elements as well as the computer system which will transmit the data in a secured manner.

The SAN a storage area network is considered to be one of the best and high speed network that can be utilized for the purpose of the storage devices as well as the hosts which will allow and perform the data that is being hosted by the different types of the storage devices. The different varieties of the block based access is being offered by the SAN it involves the several types of the devices like the HBA- host bus adapters, the hub switches, the servers as well as the disk storage.

F-2-The SAN environment 

Now a day’s the there are several numbers of the existing SANs and the entire SANS are totally based on the fibre channel. The data which is been stored by the SANs will be able to accessed through the different number of hosts which are associated with the SAN and it can be easily distributed by making use of the different file sharing protocols that are managed by the underlying host OS. The different types of the fault tolerance features such as the RADI are been supported by the storage devices which belongs to the SAN and these are even capable of carrying out the data reproduction process.

The necessity of storage security

It is being proved that the storage networks are having more number of advantages and it is even facing many challenges related to the security and for this reason the networked storage is facing different types of risks. There are different types of key aspects that are related to the networked storage which are as follows:

• The strategies which are secured outside will protect the networked storage from different types of the external threats and attacks, only implementing the strategies will not be sufficient to protect data and if the security violations are reduced then the data can be protected.
• The different types of the internal attacks are making the data storage process more violated and if the different types of the servers are being used according to storage requirements then the data can be easily secured. 

 The overview of networked storage technologies and security

SNIA the storage networking industry association argued that the issues of the storage security are facing many failures because the aspects of the security as well as the storage are not such easy to understand. There is a necessity of establishing the networked storage security which is based on the technologies related to the networked storage that gives the proper solution to the security risks.