TW201427390A - Inverse proxy system and method - Google Patents
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本發明係關於一種反向代理技術，尤其是關於一種應用於網路影音(internet video/audio)之反向代理系統及其代理方法。 The present invention relates to a reverse proxy technology, and more particularly to a reverse proxy system for internet video/audio and its proxy method.
隨著網路蓬勃發展及IP訊務(IP traffic)技術成熟，且為了因應網路影音持續增加的趨勢，網路服務提供者往往建置大量的反向代理伺服器(Reverse Proxy，以下簡稱伺服器)以降低頻寬消耗；此外，網路服務提供者也同時致力於網路影音加值應用來服務用戶，近年來網路服務提供者是採用HTTP-based adaptive bit-rate streaming技術提供影片，把影片壓製成多種位元率(bitrate)並進行切片，以依據用戶觀看進度和可用頻寬來給予合適片段，然而這樣的技術卻容易增加影片的儲存空間，同時也因此造成反向代理伺服器的儲存空間的浪費。因此，伺服器之間如何有效地進行組織與分工，以在降低頻寬消耗的同時，也能減少儲存空間的浪費，便成為網路服務的重要議題。 With the rapid development of the Internet and the mature IP traffic technology, and in response to the continuous increase of network video, network service providers often build a large number of reverse proxy servers (Reverse Proxy, hereinafter referred to as servo). In order to reduce bandwidth consumption; in addition, Internet service providers are also committed to network video and audio value-added applications to serve users. In recent years, network service providers have used HTTP-based adaptive bit-rate streaming technology to provide video. The video is compressed into a variety of bitrates and sliced to give the appropriate segments based on the user's viewing progress and available bandwidth. However, such techniques tend to increase the storage space of the movie, and thus cause a reverse proxy server. Waste of storage space. Therefore, how to effectively organize and divide the servers between servers can reduce the waste of storage space and reduce the waste of storage space, which becomes an important issue of network services.
如第1A和1B圖所示，係說明現有反向代理技術之主要具體實施的示意圖，於第1A圖中，代理伺服器叢集5包含代理伺服器51、52、53，此數量僅為舉例說明，實施時不以此為限，各代理伺服器51、52、53之間是獨立作業的，其中，代理伺服器51、52、53可用於處理請求內容， 且可儲存檔案(如影片檔案)A1、A2、A3等，當用戶70提出請求時，透過輪詢式(round robin)網域名稱系統(DNS)伺服器進行分配，例如，用戶70由第一代理伺服器51來進行服務，若第一代理伺服器51中已儲存有所要求影片，則由第一代理伺服器51提供該影片，若未儲存有該影片，則可至原站(original site)伺服器8取得並儲存該影片於第一代理伺服器51，之後，用戶71、72、73提出請求後，則依輪詢式分配至各代理伺服器51、52、53(如圖箭頭所示)，然而此代理機制可能導致每一代理伺服器51、52、53儲存有相同影片內容，最糟糕甚至是每一代理伺服器51、52、53都儲存相同影片(如圖所示)，如此不僅造成儲存空間造成浪費，且增加新的代理伺服器時也無助於提升快取命中率。 As shown in FIGS. 1A and 1B, a schematic diagram illustrating the main implementation of the existing reverse proxy technology is illustrated. In FIG. 1A, the proxy server cluster 5 includes proxy servers 51, 52, and 53. This number is merely an example. The implementation is not limited thereto, and the proxy servers 51, 52, 53 are independently operated, wherein the proxy servers 51, 52, 53 can be used to process the requested content. And can store files (such as video files) A1, A2, A3, etc., when the user 70 makes a request, distributes through a round robin Domain Name System (DNS) server, for example, the user 70 is first The proxy server 51 performs the service. If the requested video has been stored in the first proxy server 51, the video is provided by the first proxy server 51. If the movie is not stored, the original site can be accessed. The server 8 acquires and stores the movie on the first proxy server 51, and after the user 71, 72, 73 makes a request, it is distributed to each proxy server 51, 52, 53 by polling (as shown by the arrow) However, this proxy mechanism may cause each proxy server 51, 52, 53 to store the same movie content, and even worse, each proxy server 51, 52, 53 stores the same movie (as shown). This not only causes waste of storage space, but also does not help to improve the cache hit rate when adding a new proxy server.
於第1B圖中，代理伺服器叢集6包含代理伺服器61、62、63，此數量同樣僅是舉例說明，每一代理伺服器61、62、63可用於處理請求內容，且可儲存影片檔案A1、A2、A3等，同樣地，各代理伺服器61、62、63之間仍是獨立作業，此機制係利用(第七層)負載平衡器7來取代輪詢式DNS伺服器之工作分配，負載平衡器7可辨識用戶請求內容，並將相同請求內容交給同一代理伺服器處理，換言之，相同影片內容僅需於儲存一次，例如，當用戶70提出請求時，透過負載平衡器7分配後由第一代理伺服器61來進行服務，同樣地第一代理伺服器61已儲存有所要求影片則由第一代理伺服器61提供該影片，若未儲存有該影 片，則至原站伺服器8取得並儲存該影片於第一代理伺服器61，接著，用戶71、72所提出請求經負載平衡器7判斷後，與用戶70請求相同，則同樣會由第一代理伺服器61提供代理服務，如此將能有效提升整個快取命中率，但此代理機制於設備擴展時將受限於負載平衡器7所能提供服務能力的上限，且不僅有單點失效(Single Point of Failure)的問題，同時負載平衡器7因價格高昂，皆使此代理機制設備擴展受到許多限制。 In FIG. 1B, the proxy server cluster 6 includes proxy servers 61, 62, 63. This number is also merely an example. Each proxy server 61, 62, 63 can be used to process the requested content and can store the video file. A1, A2, A3, etc. Similarly, the proxy servers 61, 62, and 63 are still independent operations. This mechanism uses the (seventh layer) load balancer 7 instead of the polling DNS server. The load balancer 7 can recognize the content requested by the user and hand the same request content to the same proxy server for processing. In other words, the same movie content only needs to be stored once, for example, when the user 70 makes a request, it is distributed through the load balancer 7. The service is then performed by the first proxy server 61. Similarly, if the first proxy server 61 has stored the requested video, the video is provided by the first proxy server 61, if the movie is not stored. After the slice, the original station server 8 obtains and stores the movie on the first proxy server 61. Then, after the request made by the user 71, 72 is judged by the load balancer 7, the same request as the user 70 is also performed. A proxy server 61 provides proxy services, which will effectively increase the overall cache hit rate, but this proxy mechanism will be limited by the upper limit of the service capability that the load balancer 7 can provide when the device is extended, and not only has a single point of failure. (Single Point of Failure) problems, while the load balancer 7 is expensive due to the high price, this device mechanism is subject to many restrictions.
此外，現有反向代理技術並無法直接有效的處理存取次數較高的影片，導致如果該影片儲存於特定代理伺服器時，容易造成該特定代理伺服器過載的問題。 In addition, the existing reverse proxy technology cannot directly and efficiently process a movie with a high number of accesses, resulting in a problem that the specific proxy server is overloaded if the movie is stored in a specific proxy server.
因此，如何找出網路影音更佳之反向代理技術，特別是不改變現行代理機制的架構下，提出一種新的反向代理機制，同時避免現有代理機制的各項缺失，像是快取命中率問題、檔案重複儲存所造成儲存空間浪費、負載平衡器對於代理伺服器擴增時的限制、甚至是對存取次數高的檔案(如熱門內容影片)之處理方式等，實為目前亟欲解決之技術課題。 Therefore, how to find the reverse proxy technology with better network video and audio, especially the architecture without changing the current proxy mechanism, propose a new reverse proxy mechanism, while avoiding the lack of existing proxy mechanisms, such as cache hits. The problem of rate, the waste of storage space caused by repeated file storage, the limitation of the load balancer for the expansion of the proxy server, and even the processing of files with high access times (such as popular content videos), etc. Solved technical issues.
鑒於上述習知技術之缺點，本發明之目的係提供一種高快取命中率且可有效處理熱門內容影片之反向代理系統及其方法，以降低伺服器過載的發生。 In view of the above disadvantages of the prior art, it is an object of the present invention to provide a reverse proxy system and a method thereof that can efficiently process hit content and effectively process popular content movies to reduce the occurrence of server overload.
本發明之另一目的係提供一種易於水平擴展且彈性部署之反向代理系統及其方法，以有效增減反向代理系統 之系統能力與效能。 Another object of the present invention is to provide a reverse proxy system and a method thereof which are easy to horizontally expand and flexibly deployed, so as to effectively increase or decrease the reverse proxy system. System capabilities and performance.
為達成前述目的及其他目的，本發明提供一種反向代理系統，係包括：前導裝置及代理伺服器群組，其中，前導裝置係接收請求資訊，並以一分配機制轉送該請求資訊，代理伺服器群組係由複數台代理伺服器所組成，且該前導裝置所轉送之該請求資訊由該複數台代理伺服器之其中一者所接收，每一該代理伺服器包括快取單元和接取單元，其中，接取單元接收該前導裝置之請求資訊後，透過一配置演算法對該請求資訊進行計算以取得該請求資訊所請求之檔案的儲存位置，以從該檔案的儲存位置取得該檔案並回傳該檔案，其中，該檔案係儲存於該接取單元所屬代理伺服器中之對應快取單元，或其他代理伺服器中之對應快取單元。 To achieve the foregoing and other objects, the present invention provides a reverse proxy system, comprising: a preamble device and a proxy server group, wherein the preamble device receives the request information, and forwards the request information by an allocation mechanism, and the proxy server The server group is composed of a plurality of proxy servers, and the request information forwarded by the preamble device is received by one of the plurality of proxy servers, and each proxy server includes a cache unit and an access server. a unit, wherein the receiving unit receives the request information of the preamble device, and calculates the request information by using a configuration algorithm to obtain a storage location of the file requested by the request information, so as to obtain the file from the storage location of the file. And returning the file, wherein the file is stored in a corresponding cache unit in the proxy server of the access unit, or a corresponding cache unit in other proxy servers.
於另一實施態樣中，該配置演算法為一致性雜湊(consistent hash)演算法，而該分配機制為加權式輪詢分配機制。 In another embodiment, the configuration algorithm is a consistent hash algorithm, and the allocation mechanism is a weighted polling allocation mechanism.
於另一實施態樣中，於每一該代理伺服器所包括之該快取單元未儲存該請求資訊所請求之檔案時，該快取單元係由該代理伺服器群組所連接之原站伺服器取得該檔案以儲存該檔案。 In another implementation, when the cache unit included in each proxy server does not store the file requested by the request information, the cache unit is the original station connected by the proxy server group. The server retrieves the file to store the file.
於又一實施態樣中，每一該代理伺服器所包括之該接取單元係分別記錄該檔案之存取次數，以於該檔案之存取次數大於一門檻值時，標記該檔案為熱門檔案。此外，該接取單元更包括熱門暫存區，用於暫存所處理之該熱門檔 案。 In another embodiment, each of the accessing servers included in the proxy server records the access times of the files respectively, so that when the number of accesses of the file is greater than a threshold, the file is marked as popular. file. In addition, the access unit further includes a hot temporary storage area for temporarily storing the hot file processed case.
本發明復提出一種反向代理方法，係包括下列步驟：接收請求資訊、將該請求資訊轉送至複數台代理伺服器之其中一者、接收該請求資訊之代理伺服器係透過配置演算法對該請求資訊進行計算以取得該請求資訊所請求之檔案的儲存位置、以及依據該檔案的儲存位置，自該複數台代理伺服器之其中一者取得該請求資訊所請求之檔案，以回傳該檔案。 The present invention further provides a reverse proxy method, comprising the steps of: receiving request information, forwarding the request information to one of a plurality of proxy servers, and receiving, by the proxy server, the proxy server through the configuration algorithm Requesting information to be calculated to obtain a storage location of the file requested by the request information, and obtaining a file requested by the request information from one of the plurality of proxy servers according to the storage location of the file, to return the file .
於一實施態樣中，該反向代理方法更包括記錄該檔案之存取次數，以於該檔案之存取次數大於一門檻值時，標記該檔案為熱門檔案，進而暫存於處理該熱門檔案之代理伺服器之熱門暫存區。 In an implementation aspect, the reverse proxy method further includes recording the access times of the file, so that when the number of accesses of the file is greater than a threshold, the file is marked as a hot file, and then temporarily stored in the hot file. The popular staging area of the proxy server of the file.
相較於習知技術，本發明之反向代理系統及其方法，利用前導裝置輪詢機制將代理工作分配至每一代理伺服器，代理伺服器解析請求資訊後取得該請求資訊所請求之檔案的儲存位置，然後至該處取得該檔案，由於各代理伺服器中儲存檔案之快取單元是共享，因而，檔案僅需儲存一次，且依代理伺服器之效能分配之代理工作亦不會造成某一設備處理負載過重，重要的是，這樣的反向代理系統於設備擴展時受限較小，僅需調整配置演算法即可彈性部署代理伺服器；此外，本發明更提出於各代理伺服器之接取單元設置熱門暫存區，可存放常被存取的熱門影片，如此代理伺服器可縮短處理時間並降低運作負擔，因此，透過本發明之反向代理系統及其方法，將提供反向代理時更 佳處理效能，同時讓設備擴展時更具彈性，對於網路影音發展應有相當助益。 Compared with the prior art, the reverse proxy system and method thereof of the present invention allocates proxy work to each proxy server by using a preamble polling mechanism, and the proxy server parses the request information to obtain the file requested by the request information. The storage location, and then the file is obtained there. Since the cache unit storing the files in each proxy server is shared, the file only needs to be stored once, and the proxy work assigned according to the performance of the proxy server will not be caused. The processing load of a certain device is too heavy. It is important that such a reverse proxy system is less restricted when the device is extended. The proxy server can be flexibly deployed only by adjusting the configuration algorithm. In addition, the present invention is further proposed for each proxy servo. The access unit of the device sets a hot temporary storage area, which can store popular videos that are frequently accessed, so that the proxy server can shorten the processing time and reduce the operation burden, and therefore, the reverse proxy system and the method thereof are provided by the present invention. Reverse proxy Good processing performance, while making the device more flexible when expanding, should be quite helpful for the development of network audio and video.
以下藉由特定的具體實施例說明本發明之技術內容，熟悉此技藝之人士可由本說明書所揭示之內容輕易地瞭解本發明之優點與功效。然本發明亦可藉由其他不同的具體實施例加以施行或應用。 The technical contents of the present invention will be described below by way of specific embodiments, and those skilled in the art can easily understand the advantages and effects of the present invention from the contents disclosed in the present specification. However, the invention may be embodied or applied by other different embodiments.
須知，本說明書所附圖式所繪示之結構、比例、大小等，均僅用以配合說明書所揭示之內容，以供熟悉此技藝之人士之瞭解與閱讀，並非用以限定本發明可實施之限定條件，故不具技術上之實質意義，任何結構之修飾、比例關係之改變或大小之調整，在不影響本發明所能產生之功效及所能達成之目的下，均應仍落在本發明所揭示之技術內容得能涵蓋之範圍內。 It is to be understood that the structure, the proportions, the size, and the like of the present invention are intended to be used in conjunction with the disclosure of the specification, and are not intended to limit the invention. The conditions are limited, so it is not technically meaningful. Any modification of the structure, change of the proportional relationship or adjustment of the size should remain in this book without affecting the effects and the objectives that can be achieved by the present invention. The technical content disclosed in the invention can be covered.
請參閱第2圖，係本發明之反向代理系統的系統示意圖。如圖所示，本發明之反向代理系統1提供將用戶所發出之服務請求，轉發至提供服務之代理伺服器進行處理以將所請求之檔案回傳至用戶，用戶可透過使用者裝置9與代理伺服器群組11連線，而自代理伺服器群組11中的代理伺服器110、111取得各種服務，如影音服務，需說明的，本實施例僅以兩台代理伺服器110、111來說明，但實際運作時其數量是不限的，亦即可隨需求增減代理伺服器數量，其中，反向代理系統1主要包括前導裝置10及代理伺服器群組11。此外，要特別說明是，上述所稱之檔案係例 如為影音檔案，但並不以此為限，凡是可應用本發明之反向代理技術之其他型態的檔案均可適用。 Please refer to FIG. 2, which is a schematic diagram of the system of the reverse proxy system of the present invention. As shown, the reverse proxy system 1 of the present invention provides for forwarding a service request issued by a user to a proxy server providing the service for processing to return the requested file to the user, and the user can pass through the user device 9. The proxy server group 11 is connected to the proxy server 110, and the proxy server 110, 111 in the proxy server group 11 obtains various services, such as audio and video services. In this embodiment, only two proxy servers 110 are used. 111, but the actual number of operations is not limited, and the number of proxy servers can be increased or decreased as needed. The reverse proxy system 1 mainly includes a preamble device 10 and a proxy server group 11. In addition, it is necessary to specify that the above-mentioned file system is If it is an audio-visual file, but not limited to this, any other type of file to which the reverse proxy technology of the present invention can be applied can be applied.
前導裝置10係接收使用者裝置9所傳送之請求資訊，以一分配機制(如加權式輪詢分配機制等)轉送該請求資訊。具體而言，使用者裝置9可例如為智慧型行動裝置、隨身電子裝置、電腦或影音播放設備等，前導裝置10接收用戶透過使用者裝置9傳送之請求資訊，透過加權式輪詢機制以依據各代理伺服器之效能來分配代理工作，如此避免單一代理伺服器110、111過大的運作負載，換句話說，前導裝置10可透過例如一加權(weight)的方式以依據各代理伺服器之效能來分配代理工作，例如代理伺服器之效能越佳者，其加權值越高，其代理工作越多。 The preamble device 10 receives the request information transmitted by the user device 9, and forwards the request information by an allocation mechanism (such as a weighted polling allocation mechanism or the like). Specifically, the user device 9 can be, for example, a smart mobile device, a portable electronic device, a computer or a video playback device, etc., and the preamble device 10 receives the request information transmitted by the user through the user device 9 through a weighted polling mechanism. The performance of each proxy server is assigned to the proxy work, thus avoiding the excessive operational load of the single proxy server 110, 111. In other words, the preamble 10 can be based on, for example, a weighting method to determine the performance of each proxy server. To assign agent work, such as the better performance of the proxy server, the higher the weight value, the more agent work.
代理伺服器群組11係例如為一種叢集代理伺服器群組，其由複數台代理伺服器(在本實施例中係舉例為兩台代理伺服器)110、111所組成，前導裝置10將請求資訊傳送至複數台代理伺服器110、111之其中一者，其中，每一代理伺服器包括快取單元及接取單元，也就是，代理伺服器110包括接取單元1101及快取單元1102，而代理伺服器111包括接取單元1111及快取單元1112，其中，快取單元及接取單元係分別可利用如程序(process)實作。 The proxy server group 11 is, for example, a cluster proxy server group composed of a plurality of proxy servers (in this embodiment, two proxy servers) 110, 111, and the preamble 10 will request The information is transmitted to one of the plurality of proxy servers 110, 111, wherein each proxy server includes a cache unit and an access unit, that is, the proxy server 110 includes an access unit 1101 and a cache unit 1102. The proxy server 111 includes an access unit 1111 and a cache unit 1112, wherein the cache unit and the access unit are respectively implemented by using a process.
快取單元1102、1112是用於儲存檔案，亦即當複數台代理伺服器110、111可將曾經處理過之檔案儲存於其快取單元1102、1112，如此當下次再處理相同內容請求時，則無需重新下載檔案，然而快取單元1102、1112是有儲存 空間的限制，因此，快取單元無法儲存超過儲存空間的限制的檔案且因此須妥善應用快取單元的儲存空間。 The cache units 1102, 1112 are used for storing files, that is, when the plurality of proxy servers 110, 111 can store the processed files in their cache units 1102, 1112, so that when the same content request is processed next time, There is no need to re-download the file, but the cache units 1102, 1112 are stored. Space limitation, therefore, the cache unit cannot store files that exceed the limit of the storage space and therefore the storage space of the cache unit must be properly applied.
接取單元1101、1111係用於接收來自該前導裝置10之請求資訊，透過一配置演算法對該請求資訊進行計算以取得該請求資訊所請求之檔案的儲存位置，以從該檔案的儲存位置取得該檔案，進而回傳該檔案至該使用者裝置9，其中，該檔案係儲存在該接取單元1101所屬代理伺服器中之快取單元1102(亦稱為對應快取單元)，或其他代理伺服器111中之快取單元1112(亦稱為對應快取單元)。由上可知，用戶的請求資訊係透過例如加權的方式分配給各代理伺服器110、111，接取單元1101、1111透過配置演算法以計算出該請求資訊對應之檔案的儲存位置，藉此取得該檔案並回傳至使用者裝置9，其中，請求資訊可例如為檔案的URL，透過如DNS伺服器進行解析即可得到該請求資訊所請求內容為何，也就是說，接取單元1101、1111可自各代理伺服器110、111之快取單元1102、1112取回檔案，亦即快取單元1102、1112內的檔案是共享的，如此，檔案在快取單元中僅需儲存一次(一份)即可。 The receiving unit 1101, 1111 is configured to receive the request information from the preamble device 10, and calculate the request information by using a configuration algorithm to obtain a storage location of the file requested by the request information, so as to obtain a storage location of the file requested from the file. Obtaining the file, and then returning the file to the user device 9, wherein the file is stored in a cache unit 1102 (also referred to as a corresponding cache unit) in the proxy server to which the access unit 1101 belongs, or other The cache unit 1112 (also referred to as a corresponding cache unit) in the proxy server 111. As can be seen from the above, the request information of the user is allocated to each of the proxy servers 110 and 111 by, for example, weighting, and the accessing units 1101 and 1111 calculate the storage location of the file corresponding to the requested information through the configuration algorithm. The file is sent back to the user device 9, wherein the request information can be, for example, a URL of the file, and the content requested by the request information can be obtained by parsing, for example, a DNS server, that is, the access unit 1101, 1111 The files can be retrieved from the cache units 1102 and 1112 of the proxy servers 110 and 111, that is, the files in the cache units 1102 and 1112 are shared, so that the files need only be stored once in the cache unit (one copy). Just fine.
此外，前述之配置演算法可例如為一致性雜湊演算法，以依據一定規則配置檔案的儲存位置，之後當服務請求產生時，僅需分析該服務請求的請求資訊之特性(如請求資訊所載URL等)為何，即可知悉該檔案是儲存於哪一代理伺服器110、111之快取單元1102、1112內，如此不僅命中率高且無相同檔案重複儲存的問題。 In addition, the foregoing configuration algorithm may be, for example, a consistency hash algorithm to configure the storage location of the file according to certain rules, and then, when the service request is generated, only the characteristics of the request information of the service request need to be analyzed (such as the request information). URL, etc.), it can be known that the file is stored in the cache units 1102, 1112 of the proxy servers 110, 111, so that not only the hit rate is high, but also the same file is not stored repeatedly.
透過上述代理機制，可知每一檔案僅儲存於代理伺服器110、111之其中一者的快取單元1102、1112中，透過快取單元1102、1112內檔案共享機制，使得檔案僅儲存一份，可減少儲存空間的浪費。再者，對於反向代理擴展而言，因為採用一致性雜湊演算法，故對於既有代理伺服器(如110、111)的增加、刪除或異動影響不大，因此，對於代理伺服器的部署有較大彈性，且不影響原有的高命中率特性，亦無需習知所採用之價格昂貴的負載平衡器。 Through the above proxy mechanism, each file is stored in the cache units 1102 and 1112 of one of the proxy servers 110 and 111. The file sharing mechanism in the cache units 1102 and 1112 allows only one copy of the file to be stored. Can reduce the waste of storage space. Furthermore, for the reverse proxy extension, because of the consistency hash algorithm, the addition, deletion or transaction of the existing proxy server (such as 110, 111) has little effect, therefore, the deployment of the proxy server. It has greater flexibility and does not affect the original high hit rate characteristics, and does not require the expensive load balancer that is conventionally used.
請參閱第3A和3B圖，係本發明之反向代理系統具體實施的示意圖。如第3A圖所示，代理伺服器群組11係至少由代理伺服器110、111、112所組成，而代理伺服器110、111、112分別包含接取單元1101、1111、1121及快取單元1102、1112、1122，且前述各單元功能與第2圖所述相同，其中，快取單元1102、1112、1122可視為一快取單元叢集11’，基於檔案共享概念，來自原站伺服器8之每一檔案(如影片檔案)A1、A2、A3無需重覆儲存於各代理伺服器110、111、112，於本實施例中，係分別於快取單元1102、1112、1122內，用戶70~74可透過適當分配機制由任一代理伺服器110、111、112提供服務，即請求資訊通過接取單元1101、1111、1121解析後，可自快取單元1102、1112、1122之任一者取回所需要的檔案，當然，各代理伺服器110、111、112亦可透過加權式輪詢機制來服務用戶70~74。 Please refer to Figures 3A and 3B for a schematic diagram of a specific implementation of the reverse proxy system of the present invention. As shown in FIG. 3A, the proxy server group 11 is composed of at least the proxy servers 110, 111, 112, and the proxy servers 110, 111, 112 respectively include the access units 1101, 1111, 1121 and the cache unit. 1102, 1112, 1122, and the functions of the foregoing units are the same as those described in FIG. 2, wherein the cache units 1102, 1112, 1122 can be regarded as a cache unit cluster 11', based on the file sharing concept, from the original station server 8 Each of the files (such as the video files) A1, A2, and A3 need not be repeatedly stored in each of the proxy servers 110, 111, and 112. In this embodiment, the caches are respectively located in the cache units 1102, 1112, and 1122. ~74 can be served by any of the proxy servers 110, 111, 112 through an appropriate allocation mechanism, that is, the request information can be parsed by the access unit 1101, 1111, 1121, and can be any one of the cache units 1102, 1112, 1122. Retrieving the required files, of course, each proxy server 110, 111, 112 can also serve users 70-74 through a weighted polling mechanism.
於第3B圖中，代理伺服器群組11至少由代理伺服器110、111、112所組成，代理伺服器110、111、112之接 取單元1101、1111、1121及快取單元1102、1112、1122與第2圖所述相同，其中，快取單元1102、1112、1122可視為一快取單元叢集11’，其中，快取單元1112內儲存有檔案A1，當用戶70是透過第一代理伺服器110提供服務，接取單元1101利用配置演算法計算出該檔案的儲存位置為快取單元1112，故至快取單元1112取回該檔案A1，接著，用戶71是由第三代理伺服器112提供服務，用戶70和用戶71兩者請求資訊之特性相同(如請求資訊所載URL相同)，接取單元1121同樣以配置演算法當然也算出該檔案的儲存位置為快取單元1112，故至快取單元1112取回該檔案A1，由上可知，無論是來自原站伺服器8之檔案A1、A2、A3，在整個代理伺服器群組11中僅需儲存一份，因此，確實可避免儲存空間的浪費。 In FIG. 3B, the proxy server group 11 is composed of at least the proxy servers 110, 111, 112, and the proxy servers 110, 111, 112 are connected. The units 1101, 1111, 1121 and the cache units 1102, 1112, 1122 are the same as those described in FIG. 2, wherein the cache units 1102, 1112, 1122 can be regarded as a cache unit cluster 11', wherein the cache unit 1112 The file A1 is stored therein. When the user 70 provides the service through the first proxy server 110, the access unit 1101 calculates the storage location of the file as the cache unit 1112 by using the configuration algorithm, so the cache unit 1112 retrieves the file. File A1, then, user 71 is served by third proxy server 112, and both user 70 and user 71 request the same information (if the request information contains the same URL), and access unit 1121 also configures the algorithm of course. It is also calculated that the storage location of the file is the cache unit 1112, so the cache unit 1112 retrieves the file A1. From the above, it can be seen that the files A1, A2, and A3 from the original server 8 are in the entire proxy server. Only one copy needs to be stored in group 11, so it is indeed possible to avoid waste of storage space.
如第4圖所示，係本發明之反向代理系統另一實施例的系統示意圖。如圖所示，反向代理系統2同樣可提供用戶各種服務，如影音服務，其中，前導裝置20及代理伺服器群組21之各單元與第2圖所述實施形態及功能相同，故不再贅述，本實施例中，代理伺服器之接取單元復包括熱門暫存區，也就是，代理伺服器210之接取單元2101包括有熱門暫存區21011，而代理伺服器211之接取單元2111包括有熱門暫存區21111。 As shown in Fig. 4, it is a system diagram of another embodiment of the reverse proxy system of the present invention. As shown in the figure, the reverse proxy system 2 can also provide various services for the user, such as video and audio services. The units of the preamble device 20 and the proxy server group 21 are the same as those described in FIG. 2, so Further, in this embodiment, the access unit of the proxy server includes a hot temporary storage area, that is, the access unit 2101 of the proxy server 210 includes a hot temporary storage area 21011, and the proxy server 211 picks up Unit 2111 includes a hot staging area 21111.
對於經常被存取之檔案，一般希望可快速取得及避免特定快取單元的過載，本發明提出於代理伺服器210、211之接取單元2101、2111內分別設置一熱門暫存區21011、 21111，以對常被存取之檔案提供更快速服務。詳言之，接取單元2101、2111係分別記錄檔案被存取的存取次數，並且於某一檔案被存取次數大於一預設門檻值時，將該檔案標記為熱門檔案(即熱門內容)，其中，該接取單元2101、2111係分別獨立記錄存取次數，且其熱門檔案係為獨立標記，因此各接取單元中之熱門檔案可為各自獨立之檔案。之後，若任何接取單元2101、2111所處理的請求服務為該熱門檔案時，則將所處理之熱門檔案分別儲存於各自的熱門暫存區21011、21111內，如此，後續接取單元2101、2111發現其他請求服務也是請求該熱門檔案時，則直接由該熱門暫存區將所各自暫存的該熱門檔案回傳給使用者裝置9，將有助於加速取得熱門檔案。 For the files that are frequently accessed, it is generally desirable to quickly obtain and avoid the overload of the specific cache unit. The present invention proposes to set a hot temporary storage area 21011 in the access units 2101 and 2111 of the proxy servers 210 and 211, respectively. 21111, providing faster service to frequently accessed files. In detail, the access units 2101 and 2111 respectively record the number of accesses to which the file is accessed, and when the number of times the file is accessed is greater than a predetermined threshold, the file is marked as a popular file (ie, popular content). ), wherein the access units 2101 and 2111 independently record the number of accesses, and the hot files are independent tags, so the hot files in each access unit can be separate files. Then, if the request service processed by any of the access units 2101, 2111 is the hot file, the processed hot files are stored in the respective hot temporary storage areas 21011, 21111, and thus, the subsequent access unit 2101. When it is found that the other request service is also requesting the hot file, the hot file is directly transmitted back to the user device 9 by the hot temporary storage area, which will help accelerate the acquisition of the popular file.
需說明的，若有多個熱門檔案，但熱門暫存區21011、21111的空間有限，則勢必需選擇性暫存某些檔案，在此可採用先進先出(FIFO)或者最久未被使用(LRU)等概念，也可以依據使用熱門程度給予評價排序以選擇暫存使用率高者，皆可提供儲存空間有限下的處理，同理，若各代理伺服器210、211之快取單元2102、2112等也可適用前述關於儲存空間不足的處理方式。 It should be noted that if there are multiple popular files, but the space of the popular temporary storage areas 21011, 21111 is limited, it is necessary to selectively temporarily store certain files, where first-in-first-out (FIFO) or long-term unused (here) can be used ( Concepts such as LRU) can also be sorted according to the popularity level to select the one with higher temporary usage rate, and the processing can be provided under the limited storage space. Similarly, if the proxy servers 210, 211 are cached units 2102, respectively. The above-mentioned treatment method for insufficient storage space can also be applied to 2112 and the like.
此外，前述實施例皆假設檔案已儲存於各代理伺服器210、211之快取單元2102、2112中，假若接取單元2101、2111解析請求資訊後，向該請求資訊所請求之檔案的儲存位置(可能是快取單元2102、2112等一者)請求提供檔案，但發現該檔案並未儲存於快取單元2102、2112內時，例如 快取單元2102未儲存該檔案，則快取單元2102將由代理伺服器群組21所連接之原站伺服器8取回該檔案，並將該檔案儲存於快取單元2102中。惟，原站伺服器8僅是方便說明使用，並非侷限檔案必需儲存於特定伺服器內，亦可來自網際網路或其他外部儲存設備。 In addition, the foregoing embodiment assumes that the file is stored in the cache units 2102 and 2112 of each of the proxy servers 210 and 211. If the access unit 2101 and 2111 parse the request information, the storage location of the file requested by the request information is stored. (maybe one of the cache units 2102, 2112, etc.) requests to provide the file, but finds that the file is not stored in the cache units 2102, 2112, for example If the cache unit 2102 does not store the file, the cache unit 2102 retrieves the file from the original server 8 connected by the proxy server group 21, and stores the file in the cache unit 2102. However, the original server 8 is only for convenience of description. It is not limited to the file to be stored in a specific server, but also from the Internet or other external storage devices.
如第5圖所示，係為本發明之反向代理系統另一具體實施例的示意圖。於本實施例中，代理伺服器群組21內各單元及原站伺服器8與第4圖所述實施形態及功能相同，故不再贅述，本實施例中，係說明熱門檔案(即熱門內容)之應用實施例，其中，關於熱門檔案的判斷可分別由接取單元2101、2111、2121來獨立判斷。於實際運作時，各個檔案A1、A2僅會在快取單元2102、2112、2122之其中一者儲存一份，同樣無重複儲存的問題，用戶70~72可能由不同代理伺服器210、211、212來提供各種服務，如影音服務，且若接取單元2101、2111、2121已處理過熱門檔案之代理服務時，亦回將該熱門檔案暫存於接取單元2101、2111、2121之熱門暫存區(圖未示)內，舉例來說，接取單元2101、2121暫存有熱門檔案，而接取單元2111則未處理過熱門檔案，故並無暫存任何檔案。 As shown in Fig. 5, it is a schematic diagram of another specific embodiment of the reverse proxy system of the present invention. In this embodiment, the units in the proxy server group 21 and the original server 8 are the same as those in the fourth embodiment, and therefore will not be described again. In this embodiment, the hot files are displayed. The application embodiment of the content, wherein the judgment about the hot file can be independently determined by the access units 2101, 2111, and 2121, respectively. In actual operation, each file A1, A2 will only store one copy in one of the cache units 2102, 2112, 2122, and there is no problem of repeated storage, and the users 70-72 may be served by different proxy servers 210, 211, 212 to provide various services, such as audio and video services, and if the access unit 2101, 2111, 2121 has processed the proxy service of the popular file, the popular file is also temporarily stored in the access unit 2101, 2111, 2121 In the storage area (not shown), for example, the access units 2101, 2121 temporarily store the hot files, and the access unit 2111 has not processed the hot files, so there is no temporary storage of any files.
接著，配合前述第1-5圖所示之反向代理系統，以下將利用第6圖說明本發明之反向代理方法的步驟流程圖。 Next, in conjunction with the reverse proxy system shown in the above FIGS. 1-5, a flow chart of the steps of the reverse proxy method of the present invention will be described below using FIG.
於步驟S601中，係接收使用者裝置所傳送之請求資訊，亦即用戶可透過其使用者裝置向網路影音服務提供者提出如影音服務之各種服務的要求。接著進至步驟S602。 In step S601, the request information transmitted by the user device is received, that is, the user can request the network video service provider to provide various services such as video and audio services through the user device. Then it proceeds to step S602.
於步驟S602中，係將該請求資訊轉送至複數台代理伺服器之其中一者。詳言之，為了避免習知利用負載平衡器可能的單點失效問題，或者任一代理伺服器運作負載過重，關於請求資訊的服務歸屬，可透過加權式輪詢方式轉送請求資訊至複數台代理伺服器之其中一者。接著進至步驟S603。 In step S602, the request information is forwarded to one of a plurality of proxy servers. In detail, in order to avoid the possibility of using the load balancer to solve the single point failure problem, or any of the proxy servers operating overload, the service attribution of the request information can be transferred to the plurality of agents through the weighted polling method. One of the servers. Then it proceeds to step S603.
於步驟S603中，係接收該請求資訊之代理伺服器係透過配置演算法對該請求資訊進行計算以取得該請求資訊所請求之檔案的儲存位置。於本步驟中，為了避免代理伺服器重複儲存相同檔案，可透過一配置演算法進行服務工作的分配，例如採用一致性雜湊演算法，使得每個檔案儲存於各代理伺服器中，因此，收到請求資訊之代理伺服器亦可透過該一致性雜湊演算法取得該請求資訊所請求之檔案所儲存的位置。接著進至步驟S604。 In step S603, the proxy server that receives the request information calculates the request information through a configuration algorithm to obtain a storage location of the file requested by the request information. In this step, in order to prevent the proxy server from repeatedly storing the same file, a service algorithm can be allocated through a configuration algorithm, for example, using a consistent hash algorithm, so that each file is stored in each proxy server, and therefore, The proxy server requesting the information can also obtain the location where the file requested by the request information is stored through the consistency hash algorithm. Then it proceeds to step S604.
於步驟S604中，係依據該檔案的儲存位置，自該複數台代理伺服器之其中一者取得該請求資訊所請求之檔案，以傳回該檔案至該使用者裝置。於本步驟中，依據一致性雜湊演算法所得到該檔案所儲存的位置後，可至該檔案的儲存位置進行存取，其中，由於各代理伺服器所儲存之檔案具有共享概念，因而，每一檔案僅需儲存一份，但仍可由不同代理伺服器取得該檔案。 In step S604, the file requested by the request information is obtained from one of the plurality of proxy servers according to the storage location of the file, to return the file to the user device. In this step, after the location of the file is obtained according to the consistency hash algorithm, the storage location of the file can be accessed, wherein, since the files stored by the proxy servers have a sharing concept, each Only one copy of a file needs to be stored, but it can still be retrieved by a different proxy server.
於一具體實施例中，於該步驟S604中，更包括當該請求資訊所請求之檔案的儲存位置未儲存該檔案時，係自一原站伺服器取得該檔案以儲存該檔案，亦即透過一致性 雜湊演算法分配計算，檔案所在位置是固定的，因而若至該檔案儲存位置發現該檔案未儲存時，則可由如原站伺服器之外部取回該檔案，並儲存該檔案於該代理伺服器內。 In a specific embodiment, in the step S604, when the file is not stored in the storage location of the file requested by the request information, the file is obtained from an original server to store the file, that is, consistency The hash algorithm allocates calculations, and the location of the file is fixed. Therefore, if the file is not stored until the file storage location is found, the file can be retrieved from the outside of the original server, and the file is stored in the proxy server. Inside.
此外，於本實施例中，更包括記錄該檔案之存取次數，以於該檔案之存取次數大於一門檻值時，標記該檔案為熱門檔案，進而暫存於處理該熱門檔案之代理伺服器之熱門暫存區。具體而言，為解決某些檔案特別常被存取，故於各自的代理伺服器設置一熱門暫存區來暫存熱門檔案，之後代理伺服器若有該熱門檔案之服務請求時，則不需至原先儲存該熱門檔案之代理伺服器的儲存處存取該熱門檔案，即可由各自的代理伺服器之熱門暫存區提供，藉以縮短處理時間並降低運作負擔。 In addition, in this embodiment, the number of accesses of the file is recorded, so that when the number of accesses of the file is greater than a threshold, the file is marked as a hot file, and then temporarily stored in a proxy server that processes the hot file. The popular staging area of the device. Specifically, in order to solve the problem that some files are frequently accessed, a hot temporary storage area is set in the respective proxy server to temporarily store the hot file, and then the proxy server does not have the service request of the hot file. The hot file needs to be accessed from the storage server of the proxy server where the hot file was originally stored, and can be provided by the popular temporary storage area of the respective proxy server, thereby shortening the processing time and reducing the operation load.
與習知技術相比較，本發明之反向代理系統及其方法，透過加權式輪詢機制將代理服務工作分配給各代理伺服器，避免任一代理伺服器運作負載過重，而代理伺服器透過如一致性雜湊演算法由請求資訊取得所請求之檔案的儲存位置，由於各代理伺服器中所儲存之檔案是共享，因而檔案僅需儲存一份，將可避免儲存空間的浪費，如此，透過一致性雜湊演算法的使用，對於代理伺服器之增加、刪除或異動將不會造成過大影響，使得代理伺服器部署彈性較大，且不影響原有的高命中率特性，亦無成本過高的問題，且針對熱門影片的存取問題，本發明提出於各代理伺服器設置熱門暫存區，藉此存放常被存取的熱門影片，如此代理伺服器可縮短處理時間並降低運作負擔。因此， 透過本發明之反向代理系統及其方法，將使設備擴展時更有彈性，且避免現有反向代理的許多缺陷，因而對網路影音服務發展是有所助益。 Compared with the prior art, the reverse proxy system and the method thereof of the present invention distribute the proxy service work to each proxy server through a weighted polling mechanism, so as to avoid overloading the operation of any proxy server, and the proxy server transmits If the consistency hash algorithm obtains the storage location of the requested file by requesting information, since the files stored in the proxy servers are shared, only one copy of the file needs to be stored, which avoids waste of storage space. The use of the consistency hash algorithm will not have an excessive impact on the addition, deletion or transaction of the proxy server, making the proxy server deployment more flexible, without affecting the original high hit rate characteristics, and without excessive cost. The problem, and for the access problem of popular videos, the present invention proposes to set a popular temporary storage area for each proxy server, thereby storing popular videos that are frequently accessed, so that the proxy server can shorten the processing time and reduce the operation load. therefore, The reverse proxy system and method thereof of the present invention will make the device more flexible when expanding, and avoid many defects of the existing reverse proxy, thus contributing to the development of the network audio and video service.
上述實施例僅例示性說明本發明之原理及其功效，而非用於限制本發明。任何熟習此項技藝之人士均可在不違背本發明之精神及範疇下，對上述實施例進行修飾與改變。因此，本發明之權利保護範圍，應如後述之申請專利範圍所列。 The above-described embodiments are merely illustrative of the principles of the invention and its effects, and are not intended to limit the invention. Modifications and variations of the above-described embodiments can be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention should be as set forth in the scope of the claims described below.
1、2‧‧‧反向代理系統 1, 2‧‧‧ Reverse proxy system
10、20‧‧‧前導裝置 10, 20‧‧‧ lead device
11、21‧‧‧代理伺服器群組 11, 21‧‧‧Proxy server group
11’、21’‧‧‧快取單元叢集 11’, 21’‧‧‧ cache unit cluster
110、111、112、210、211、212‧‧‧代理伺服器 110, 111, 112, 210, 211, 212‧‧‧ proxy server
1101、1111、1121、2101、2111、2121‧‧‧接取單元 1101, 1111, 1121, 2101, 2111, 2121‧‧‧ access unit
1102、1112、1122、2102、2112、2122‧‧‧快取單元 1102, 1112, 1122, 2102, 2112, 2122‧‧‧ cache unit
21011、21111‧‧‧熱門暫存區 21011, 21111‧‧‧ Popular Temporary Storage Area
5、6‧‧‧代理伺服器叢集 5, 6‧‧‧Proxy server cluster
51、52、53、61、62、63‧‧‧代理伺服器 51, 52, 53, 61, 62, 63‧‧ ‧ proxy server
7‧‧‧負載平衡器 7‧‧‧Load balancer
70~74‧‧‧用戶 70~74‧‧‧Users
8‧‧‧原站伺服器 8‧‧‧ original station server
9‧‧‧使用者裝置 9‧‧‧User device
S601~S604‧‧‧步驟 S601~S604‧‧‧Steps
A1、A2、A3‧‧‧檔案、影片檔案 A1, A2, A3‧‧‧ files, video files
第1A和1B圖係說明現有反向代理技術之主要具體實施的示意圖；第2圖係說明本發明之反向代理系統的系統示意圖；第3A和3B圖係說明本發明之反向代理系統具體實施的示意圖；第4圖係說明本發明之反向代理系統另一實施例的系統示意圖；第5圖係說明本發明之反向代理系統另一具體實施例的示意圖；以及第6圖係說明本發明之反向代理方法的步驟流程圖。 1A and 1B are diagrams showing the main implementation of the existing reverse proxy technology; FIG. 2 is a schematic diagram showing the system of the reverse proxy system of the present invention; and FIGS. 3A and 3B are diagrams illustrating the reverse proxy system of the present invention. FIG. 4 is a schematic diagram showing a system of another embodiment of the reverse proxy system of the present invention; FIG. 5 is a schematic diagram showing another embodiment of the reverse proxy system of the present invention; and FIG. A flow chart of the steps of the reverse proxy method of the present invention.
1‧‧‧反向代理系統 1‧‧‧Reverse proxy system
10‧‧‧前導裝置 10‧‧‧Preamble
11‧‧‧代理伺服器群組 11‧‧‧Proxy server group
110、111‧‧‧代理伺服器 110, 111‧‧‧Proxy server
1101、1111‧‧‧接取單元 1101, 1111‧‧‧ access unit
1102、1112‧‧‧快取單元 1102, 1112‧‧‧ cache unit
9‧‧‧使用者裝置 9‧‧‧User device
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