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Confidentiality and authentication are primary concerns of RFID (Radio Frequency IDentification) based identification systems. Low cost, non sight-line scanning capability, unique identification and functional haste make RFID systems much more suitable for supply chain management and IoT networks, compare to barcodes and magnetic tapes. Since, RFID tags can be scanned from a greater distance over a radio channel which is easily accessible for adversaries, therefore numerous Ultralightweight Mutual Authentication Protocols (UMAPs) have been proposed to ensure the security of the RFID systems in a cost effective way. These UMAPs mainly involve low cost bitwise logical ( $$Triangular$$ ) operations such as $$XOR, AND OR$$ etc., usually these logical operations offer poor diffusion properties and hence result in disclosure of the concealed secrets. Almost all of the previous UMAPs have certain pitfalls and reported to be susceptible to Denial of Service, traceability, full disclosure and cloning attacks. In this paper, we propose a new UMAP that is resilient to structured and unstructured cryptanalysis techniques. The proposed Ultralightweight Resilient Mutual Authentication Protocol (URMAP) avoids all the pitfalls and unbalanced operators in its design that were the main reasons of failure of previous UMAPs. The incorporation of ultralightweight primitives; $$Per{\text{-}}XOR$$ ( $${P}_{x})$$ and $$Inverse Per{\text{-}}XOR$$ $$({ P}_{x}^{-1})$$ makes the protocol messages more resistant to all types of adversaries. The security and privacy capabilities of URMAP are evaluated through formal analysis. The results of GNY Logic analysis prove that the proposed protocol is resilient to all possible attack scenarios thus ensuring optimal confidentiality, integrity and availability services.

We report a case of sarcoidosis with severe cholestasis and cholangiographic features of sclerosing cholangitis that responded dramatically to corticosteroid therapy. Although an association between sarcoidosis and primary sclerosing cholangitis has been suggested by previous reports, features suggestive of primary sclerosing cholangitis, including inflammatory bowel disease, hepatic histology and serum neutrophil cytoplasmic antibodies, were absent in this case. Cholangiography may be useful in the evaluation of patients with cholestatic sarcoid liver disease, and intrahepatic biliary strictures should be included in the spectrum of hepatic involvement by sarcoidosis. A trial of corticosteroid therapy may be of benefit in patients with bile ductal involvement by sarcoidosis.