摘要:WirelessPANs(2)The802.15workinggroupisdefiningdifferentversionsfordevicesthathavedifferentrequirements.802.15.3focusesonhigh-bandwidth(about55Mbit/sec),low-powerMACandphysicallayers,while802.15.4dealswithlow-bandwidth(about250Kbit/sec),extra-lowpowerMACandphy
Wireless PANs(2)
The 802.15 working group is defining different versions for devices that have different requirements. 802.15.3 focuses on high-bandwidth (about 55M bit/sec), low-power MAC and physical layers, while 802.15.4 deals with low-bandwidth (about 250K bit/sec), extra-low power MAC and physical layers.
The emphasis on minimizing cost, complexity and chip size is permeating all aspects of the standardization process. The selection criteria for power management, security algorithms and QoS all include consideration of these features. The short-range nature of communication in a wireless PAN also means reduced transmission power and cost.
The security requirements for 802.15 networks are different from more static networks because of the dynamic nature of wireless PANs. As a result, the working group is looking into specifying public-key solutions for authentication and key exchange, letting devices that have not been in contact previously establish secure communications without revealing any secret keying material.
Once the devices have been authenticated, each device in the wireless PAN shares common group (symmetric) payload protection keys for encryption and data integrity. Devices also may use the authentication mechanism to establish two-party secure subnetworks.
Another issue still facing the working group before completion of the standards is coexistence with other types of wireless devices and among the different types of 802.15 devices. There are several wireless standards that specify transmission in the 2.4-GHz range, and in some cases they interfere with each other.
Despite the remaining challenges, the working group expects to resolve the outstanding issues and provide complete, cost-effective, low-power solutions in the wireless device market.
The standards are scheduled to be completed in the third quarter of this year.
[參考譯文]
無線個人區(qū)域網 (2)
802.15工作組正在為有不同要求的設備定義不同的版本。802.15.3針對大帶寬(約55M位/秒)、低功率MAC和物理層,而802.15.4針對小帶寬(約250K位/秒)和極低功率的MAC和物理層。
在此標準化過程的方方面面都貫穿著對降低成本、復雜度和芯片尺寸的強調。用電管理、安全算法和 QoS的選擇標準全都考慮到這些特點。無線PAN的短距離通信的本質也意味著降低了發(fā)射功率和成本。
由于無線 PAN具有動態(tài)的本質,802.15網絡的安全要求不同于更多的靜態(tài)網絡。因此,該工作組正在為認證和密鑰交換的公開密鑰方案做深入的研究,以便讓以前沒有接觸過的設備在不暴露任何密鑰材料的情況下建立安全的通信。
一旦設備得到認證,無線 PAN中的每臺設備就共享用于加密和數(shù)據完整性的公共組(對稱)有效負荷保護密鑰。設備也能使用認證機制,建立兩方的安全子網。
工作組在完成此標準之前還面臨著另一個問題,即與其他類型的無線設備和在不同類型的 802.15設備之間的共處問題。在2.4GHz波段已有幾個闡明發(fā)射的無線標準,在某些情況下,這些標準互相有干擾。
盡管還存在著挑戰(zhàn),但工作組期待著解決這些突出的問題,為無線設備市場提供完整的、有效的、低功率的解決方案。
此標準預定在今年第三季度完成。
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